Fill in the boxes to get the right equation

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP











up vote
2
down vote

favorite












Here is a math puzzle I had a little bit of hard time with




Blockquote




No computers please



There is a solution without inverting 6 to 9










share|improve this question























  • With regard to operator order on the left hand side, is the division performed first, followed by the subtraction and then the addition?
    – hexomino
    2 hours ago










  • Yes division before addition or subtraction
    – DEEM
    2 hours ago










  • Glad you included the "no computers please" line :P
    – user477343
    2 hours ago






  • 1




    This is my own puzzle @Gareth McCaughan. My Grandapa told me!!
    – DEEM
    1 hour ago






  • 1




    @user477343 there is: I have just found one.
    – Weather Vane
    32 mins ago















up vote
2
down vote

favorite












Here is a math puzzle I had a little bit of hard time with




Blockquote




No computers please



There is a solution without inverting 6 to 9










share|improve this question























  • With regard to operator order on the left hand side, is the division performed first, followed by the subtraction and then the addition?
    – hexomino
    2 hours ago










  • Yes division before addition or subtraction
    – DEEM
    2 hours ago










  • Glad you included the "no computers please" line :P
    – user477343
    2 hours ago






  • 1




    This is my own puzzle @Gareth McCaughan. My Grandapa told me!!
    – DEEM
    1 hour ago






  • 1




    @user477343 there is: I have just found one.
    – Weather Vane
    32 mins ago













up vote
2
down vote

favorite









up vote
2
down vote

favorite











Here is a math puzzle I had a little bit of hard time with




Blockquote




No computers please



There is a solution without inverting 6 to 9










share|improve this question















Here is a math puzzle I had a little bit of hard time with




Blockquote




No computers please



There is a solution without inverting 6 to 9







mathematics lateral-thinking no-computers formation-of-numbers






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 48 mins ago









GentlePurpleRain♦

16k565132




16k565132










asked 2 hours ago









DEEM

3,8651074




3,8651074











  • With regard to operator order on the left hand side, is the division performed first, followed by the subtraction and then the addition?
    – hexomino
    2 hours ago










  • Yes division before addition or subtraction
    – DEEM
    2 hours ago










  • Glad you included the "no computers please" line :P
    – user477343
    2 hours ago






  • 1




    This is my own puzzle @Gareth McCaughan. My Grandapa told me!!
    – DEEM
    1 hour ago






  • 1




    @user477343 there is: I have just found one.
    – Weather Vane
    32 mins ago

















  • With regard to operator order on the left hand side, is the division performed first, followed by the subtraction and then the addition?
    – hexomino
    2 hours ago










  • Yes division before addition or subtraction
    – DEEM
    2 hours ago










  • Glad you included the "no computers please" line :P
    – user477343
    2 hours ago






  • 1




    This is my own puzzle @Gareth McCaughan. My Grandapa told me!!
    – DEEM
    1 hour ago






  • 1




    @user477343 there is: I have just found one.
    – Weather Vane
    32 mins ago
















With regard to operator order on the left hand side, is the division performed first, followed by the subtraction and then the addition?
– hexomino
2 hours ago




With regard to operator order on the left hand side, is the division performed first, followed by the subtraction and then the addition?
– hexomino
2 hours ago












Yes division before addition or subtraction
– DEEM
2 hours ago




Yes division before addition or subtraction
– DEEM
2 hours ago












Glad you included the "no computers please" line :P
– user477343
2 hours ago




Glad you included the "no computers please" line :P
– user477343
2 hours ago




1




1




This is my own puzzle @Gareth McCaughan. My Grandapa told me!!
– DEEM
1 hour ago




This is my own puzzle @Gareth McCaughan. My Grandapa told me!!
– DEEM
1 hour ago




1




1




@user477343 there is: I have just found one.
– Weather Vane
32 mins ago





@user477343 there is: I have just found one.
– Weather Vane
32 mins ago











5 Answers
5






active

oldest

votes

















up vote
1
down vote













how about




$25-9+12/6=3times6$




to do that




I rotated 6 into 9 as you suspected which is valid for the tag provided.







share|improve this answer


















  • 1




    I didn't copy this - didn't notice - UV.
    – Weather Vane
    1 hour ago










  • @WeatherVane np :)
    – Oray
    1 hour ago










  • Happy that you reached the same conclusion.
    – Weather Vane
    1 hour ago


















up vote
1
down vote













This answer follows by BODMAS or BEDMAS or PEDMAS.




Umm...




THERE IS NO SOLUTION! (without lateral thinking; without inverting the $6$, for example)




Let's call the numbers we can choose from, the Option Numbers.





25 cannot be in the third and fourth box.




Proof:




This is our equation: $$Box-Box+Box:/:Box=BoxtimesBox.tag$small rm given$$$ $12$, $6$ and $3$ do not divide $25$, so the third box can only be $25$ if the fourth box is $25$. Suppose that involves a solution. Then we have $$Box - Box + 1 = Boxtimes Box.$$







The largest number for the left hand side is $25-3+1=23$ so the right hand side cannot be greater than $23$. But $23$ is prime and both $22$ and $21$ have two distinct prime factors (although none of option numbers are prime), so the RHS cannot be greater than $20$.

Also, $20=5times 4 = 10times 2$ which uses none of the option numbers as well, and since $19$ is prime, that means the RHS cannot be greater than $18$. But also, every other product strictly involving the option numbers is greater than $18$, so the RHS cannot be lower than $18$ either.

If the RHS cannot be greater or lower than $18$, then it is equal to $18$. $$Box-Box+Box:/:Box=18.tag*$(3times 6$ or $6times 3)$$$







Now $18=6times 3$ which uses two of the option numbers. So now we must find option numbers such that $$Box-Box+1=boxed6times boxed3 =18$$ Therefore $Box-Box=18-1=17$. Of course the first box has to have a bigger value than $17$, because $17$ is positive and all the option numbers are positive. The only option number bigger than $17$ is $25$. Therefore the second box has a value of $25-17=8$ but $8$ is not an option number.

This is a contradiction, so $25$ cannot be in the third box, and thus fourth one, too.








$Box:/:Box=2$ or $4$.




Proof:




Now $Box:/: Box$ has to be an integer since $18$ is an integer, therefore the numerator box (third one) has an option number greater than the denominator box (fourth one). Since $3$ is the lowest option number, then $3$ cannot be in the third box. That leaves $12$ or $6$, so that leaves the fourth box to be $6$ or $3$. Therefore, this fraction must be equal to $12/6$, $6/3$ or $12/3$ which is $2$, $2$ or $4$. And since $2=2$, then the fraction is either $2$ or $4$.







We thus have the equations: $$beginalignBox-Box+2&=18 \ smallrm or quad Box-Box+4&=18.endalign$$ Therefore, $$beginalignBox-Box&=18-2=16 \ smallrm or quad Box-Box&=18-4=12.endalign$$





And finally,




From the previous proof, THERE EXISTS NO SOLUTION!




Proof:




Now considering the first equation, the first box has to have an option number greater than $16$. The only option number like that is $25$. We thus have $$25-Box=16$$ therefore $Box=25-16=9$. But $9$ is not an option number. That is a contradiction, so the first equation cannot exist. $$requirecancelxcancel Box-Box=16$$







Considering the second equation, the first box needs to be greater than $12$. It can't be $12$, it has to be greater than $12$. Again, the only option number greater than $12$ is $25$. We thus have $$25-Box=12$$ therefore $Box=25-12=13$. But $13$ is not an option number. That is a contradiction so the second equation cannot exist. $$requirecancelxcancel Box-Box=12$$ But if both equations cannot exist, then...







...THERE IS NO SOLUTION!





Therefore,




Some lateral-thinking must be required, unless you do not follow by BODMAS or BEDMAS or PEDMAS.







share|improve this answer






















  • check the tags in the question :)
    – Oray
    1 hour ago











  • @Oray I did, but DEEM wrote that he/she found a solution without inverting a $6$ to a $9$, and I cannot think of anything else more lateral :P
    – user477343
    1 hour ago











  • @user477343 This is a great answer, and though I hate to do so, I can't help it because it's driving me crazy lol; your OOP is incorrect. PEMDAS is what you're looking for. Multiplication always comes prior to division.
    – PerpetualJ
    13 mins ago


















up vote
1
down vote













My solution is




$25 - 12 + 25 / 3 = 3 times 6$




because




the numbers are octal base, and converting to decimal base




gives




$21 - 10 + 21 / 3 = 3 times 6$







share|improve this answer






















  • I have already submitted this answer -.-
    – Oray
    1 hour ago










  • @Oray this is a new, different answer.
    – Weather Vane
    44 mins ago

















up vote
0
down vote













Using the tag:




Each number must be used. It seems like there are 4 numbers: 12, 6, 25, 3. However, I'm guessing there are 6 numbers (lateral thinking): 1, 2, 6, 2, 5, 3. So one of the answers (there may be more with this logic): is

6 - 5 + 3 / 1 = 2 * 2

3 - 5 + 6 / 1 = 2 * 2 is another order







share|improve this answer





























    up vote
    0
    down vote













    There doesn't seem to be anything that says that only one number can be placed into each box. Thus




    $$12 - 25 + 66 div 3 = 3 times 3$$




    would be a valid solution.



    It just requires putting




    two $6$s in the same box.







    share|improve this answer




















    • @Gareth I just saw your comment on the question above, after posting this solution. I'm surprised you didn't post an answer yourself!
      – GentlePurpleRain♦
      14 mins ago










    • OP responded "No more than one number in the square please"
      – Greg
      5 mins ago










    • @Greg: I'm only putting one number in each; I'm just putting one number twice in one of them... :P (This is a valid answer to the question as posed. That criterion was not in the question.)
      – GentlePurpleRain♦
      12 secs ago










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    5 Answers
    5






    active

    oldest

    votes








    5 Answers
    5






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes








    up vote
    1
    down vote













    how about




    $25-9+12/6=3times6$




    to do that




    I rotated 6 into 9 as you suspected which is valid for the tag provided.







    share|improve this answer


















    • 1




      I didn't copy this - didn't notice - UV.
      – Weather Vane
      1 hour ago










    • @WeatherVane np :)
      – Oray
      1 hour ago










    • Happy that you reached the same conclusion.
      – Weather Vane
      1 hour ago















    up vote
    1
    down vote













    how about




    $25-9+12/6=3times6$




    to do that




    I rotated 6 into 9 as you suspected which is valid for the tag provided.







    share|improve this answer


















    • 1




      I didn't copy this - didn't notice - UV.
      – Weather Vane
      1 hour ago










    • @WeatherVane np :)
      – Oray
      1 hour ago










    • Happy that you reached the same conclusion.
      – Weather Vane
      1 hour ago













    up vote
    1
    down vote










    up vote
    1
    down vote









    how about




    $25-9+12/6=3times6$




    to do that




    I rotated 6 into 9 as you suspected which is valid for the tag provided.







    share|improve this answer














    how about




    $25-9+12/6=3times6$




    to do that




    I rotated 6 into 9 as you suspected which is valid for the tag provided.








    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited 2 hours ago

























    answered 2 hours ago









    Oray

    14.4k435141




    14.4k435141







    • 1




      I didn't copy this - didn't notice - UV.
      – Weather Vane
      1 hour ago










    • @WeatherVane np :)
      – Oray
      1 hour ago










    • Happy that you reached the same conclusion.
      – Weather Vane
      1 hour ago













    • 1




      I didn't copy this - didn't notice - UV.
      – Weather Vane
      1 hour ago










    • @WeatherVane np :)
      – Oray
      1 hour ago










    • Happy that you reached the same conclusion.
      – Weather Vane
      1 hour ago








    1




    1




    I didn't copy this - didn't notice - UV.
    – Weather Vane
    1 hour ago




    I didn't copy this - didn't notice - UV.
    – Weather Vane
    1 hour ago












    @WeatherVane np :)
    – Oray
    1 hour ago




    @WeatherVane np :)
    – Oray
    1 hour ago












    Happy that you reached the same conclusion.
    – Weather Vane
    1 hour ago





    Happy that you reached the same conclusion.
    – Weather Vane
    1 hour ago











    up vote
    1
    down vote













    This answer follows by BODMAS or BEDMAS or PEDMAS.




    Umm...




    THERE IS NO SOLUTION! (without lateral thinking; without inverting the $6$, for example)




    Let's call the numbers we can choose from, the Option Numbers.





    25 cannot be in the third and fourth box.




    Proof:




    This is our equation: $$Box-Box+Box:/:Box=BoxtimesBox.tag$small rm given$$$ $12$, $6$ and $3$ do not divide $25$, so the third box can only be $25$ if the fourth box is $25$. Suppose that involves a solution. Then we have $$Box - Box + 1 = Boxtimes Box.$$







    The largest number for the left hand side is $25-3+1=23$ so the right hand side cannot be greater than $23$. But $23$ is prime and both $22$ and $21$ have two distinct prime factors (although none of option numbers are prime), so the RHS cannot be greater than $20$.

    Also, $20=5times 4 = 10times 2$ which uses none of the option numbers as well, and since $19$ is prime, that means the RHS cannot be greater than $18$. But also, every other product strictly involving the option numbers is greater than $18$, so the RHS cannot be lower than $18$ either.

    If the RHS cannot be greater or lower than $18$, then it is equal to $18$. $$Box-Box+Box:/:Box=18.tag*$(3times 6$ or $6times 3)$$$







    Now $18=6times 3$ which uses two of the option numbers. So now we must find option numbers such that $$Box-Box+1=boxed6times boxed3 =18$$ Therefore $Box-Box=18-1=17$. Of course the first box has to have a bigger value than $17$, because $17$ is positive and all the option numbers are positive. The only option number bigger than $17$ is $25$. Therefore the second box has a value of $25-17=8$ but $8$ is not an option number.

    This is a contradiction, so $25$ cannot be in the third box, and thus fourth one, too.








    $Box:/:Box=2$ or $4$.




    Proof:




    Now $Box:/: Box$ has to be an integer since $18$ is an integer, therefore the numerator box (third one) has an option number greater than the denominator box (fourth one). Since $3$ is the lowest option number, then $3$ cannot be in the third box. That leaves $12$ or $6$, so that leaves the fourth box to be $6$ or $3$. Therefore, this fraction must be equal to $12/6$, $6/3$ or $12/3$ which is $2$, $2$ or $4$. And since $2=2$, then the fraction is either $2$ or $4$.







    We thus have the equations: $$beginalignBox-Box+2&=18 \ smallrm or quad Box-Box+4&=18.endalign$$ Therefore, $$beginalignBox-Box&=18-2=16 \ smallrm or quad Box-Box&=18-4=12.endalign$$





    And finally,




    From the previous proof, THERE EXISTS NO SOLUTION!




    Proof:




    Now considering the first equation, the first box has to have an option number greater than $16$. The only option number like that is $25$. We thus have $$25-Box=16$$ therefore $Box=25-16=9$. But $9$ is not an option number. That is a contradiction, so the first equation cannot exist. $$requirecancelxcancel Box-Box=16$$







    Considering the second equation, the first box needs to be greater than $12$. It can't be $12$, it has to be greater than $12$. Again, the only option number greater than $12$ is $25$. We thus have $$25-Box=12$$ therefore $Box=25-12=13$. But $13$ is not an option number. That is a contradiction so the second equation cannot exist. $$requirecancelxcancel Box-Box=12$$ But if both equations cannot exist, then...







    ...THERE IS NO SOLUTION!





    Therefore,




    Some lateral-thinking must be required, unless you do not follow by BODMAS or BEDMAS or PEDMAS.







    share|improve this answer






















    • check the tags in the question :)
      – Oray
      1 hour ago











    • @Oray I did, but DEEM wrote that he/she found a solution without inverting a $6$ to a $9$, and I cannot think of anything else more lateral :P
      – user477343
      1 hour ago











    • @user477343 This is a great answer, and though I hate to do so, I can't help it because it's driving me crazy lol; your OOP is incorrect. PEMDAS is what you're looking for. Multiplication always comes prior to division.
      – PerpetualJ
      13 mins ago















    up vote
    1
    down vote













    This answer follows by BODMAS or BEDMAS or PEDMAS.




    Umm...




    THERE IS NO SOLUTION! (without lateral thinking; without inverting the $6$, for example)




    Let's call the numbers we can choose from, the Option Numbers.





    25 cannot be in the third and fourth box.




    Proof:




    This is our equation: $$Box-Box+Box:/:Box=BoxtimesBox.tag$small rm given$$$ $12$, $6$ and $3$ do not divide $25$, so the third box can only be $25$ if the fourth box is $25$. Suppose that involves a solution. Then we have $$Box - Box + 1 = Boxtimes Box.$$







    The largest number for the left hand side is $25-3+1=23$ so the right hand side cannot be greater than $23$. But $23$ is prime and both $22$ and $21$ have two distinct prime factors (although none of option numbers are prime), so the RHS cannot be greater than $20$.

    Also, $20=5times 4 = 10times 2$ which uses none of the option numbers as well, and since $19$ is prime, that means the RHS cannot be greater than $18$. But also, every other product strictly involving the option numbers is greater than $18$, so the RHS cannot be lower than $18$ either.

    If the RHS cannot be greater or lower than $18$, then it is equal to $18$. $$Box-Box+Box:/:Box=18.tag*$(3times 6$ or $6times 3)$$$







    Now $18=6times 3$ which uses two of the option numbers. So now we must find option numbers such that $$Box-Box+1=boxed6times boxed3 =18$$ Therefore $Box-Box=18-1=17$. Of course the first box has to have a bigger value than $17$, because $17$ is positive and all the option numbers are positive. The only option number bigger than $17$ is $25$. Therefore the second box has a value of $25-17=8$ but $8$ is not an option number.

    This is a contradiction, so $25$ cannot be in the third box, and thus fourth one, too.








    $Box:/:Box=2$ or $4$.




    Proof:




    Now $Box:/: Box$ has to be an integer since $18$ is an integer, therefore the numerator box (third one) has an option number greater than the denominator box (fourth one). Since $3$ is the lowest option number, then $3$ cannot be in the third box. That leaves $12$ or $6$, so that leaves the fourth box to be $6$ or $3$. Therefore, this fraction must be equal to $12/6$, $6/3$ or $12/3$ which is $2$, $2$ or $4$. And since $2=2$, then the fraction is either $2$ or $4$.







    We thus have the equations: $$beginalignBox-Box+2&=18 \ smallrm or quad Box-Box+4&=18.endalign$$ Therefore, $$beginalignBox-Box&=18-2=16 \ smallrm or quad Box-Box&=18-4=12.endalign$$





    And finally,




    From the previous proof, THERE EXISTS NO SOLUTION!




    Proof:




    Now considering the first equation, the first box has to have an option number greater than $16$. The only option number like that is $25$. We thus have $$25-Box=16$$ therefore $Box=25-16=9$. But $9$ is not an option number. That is a contradiction, so the first equation cannot exist. $$requirecancelxcancel Box-Box=16$$







    Considering the second equation, the first box needs to be greater than $12$. It can't be $12$, it has to be greater than $12$. Again, the only option number greater than $12$ is $25$. We thus have $$25-Box=12$$ therefore $Box=25-12=13$. But $13$ is not an option number. That is a contradiction so the second equation cannot exist. $$requirecancelxcancel Box-Box=12$$ But if both equations cannot exist, then...







    ...THERE IS NO SOLUTION!





    Therefore,




    Some lateral-thinking must be required, unless you do not follow by BODMAS or BEDMAS or PEDMAS.







    share|improve this answer






















    • check the tags in the question :)
      – Oray
      1 hour ago











    • @Oray I did, but DEEM wrote that he/she found a solution without inverting a $6$ to a $9$, and I cannot think of anything else more lateral :P
      – user477343
      1 hour ago











    • @user477343 This is a great answer, and though I hate to do so, I can't help it because it's driving me crazy lol; your OOP is incorrect. PEMDAS is what you're looking for. Multiplication always comes prior to division.
      – PerpetualJ
      13 mins ago













    up vote
    1
    down vote










    up vote
    1
    down vote









    This answer follows by BODMAS or BEDMAS or PEDMAS.




    Umm...




    THERE IS NO SOLUTION! (without lateral thinking; without inverting the $6$, for example)




    Let's call the numbers we can choose from, the Option Numbers.





    25 cannot be in the third and fourth box.




    Proof:




    This is our equation: $$Box-Box+Box:/:Box=BoxtimesBox.tag$small rm given$$$ $12$, $6$ and $3$ do not divide $25$, so the third box can only be $25$ if the fourth box is $25$. Suppose that involves a solution. Then we have $$Box - Box + 1 = Boxtimes Box.$$







    The largest number for the left hand side is $25-3+1=23$ so the right hand side cannot be greater than $23$. But $23$ is prime and both $22$ and $21$ have two distinct prime factors (although none of option numbers are prime), so the RHS cannot be greater than $20$.

    Also, $20=5times 4 = 10times 2$ which uses none of the option numbers as well, and since $19$ is prime, that means the RHS cannot be greater than $18$. But also, every other product strictly involving the option numbers is greater than $18$, so the RHS cannot be lower than $18$ either.

    If the RHS cannot be greater or lower than $18$, then it is equal to $18$. $$Box-Box+Box:/:Box=18.tag*$(3times 6$ or $6times 3)$$$







    Now $18=6times 3$ which uses two of the option numbers. So now we must find option numbers such that $$Box-Box+1=boxed6times boxed3 =18$$ Therefore $Box-Box=18-1=17$. Of course the first box has to have a bigger value than $17$, because $17$ is positive and all the option numbers are positive. The only option number bigger than $17$ is $25$. Therefore the second box has a value of $25-17=8$ but $8$ is not an option number.

    This is a contradiction, so $25$ cannot be in the third box, and thus fourth one, too.








    $Box:/:Box=2$ or $4$.




    Proof:




    Now $Box:/: Box$ has to be an integer since $18$ is an integer, therefore the numerator box (third one) has an option number greater than the denominator box (fourth one). Since $3$ is the lowest option number, then $3$ cannot be in the third box. That leaves $12$ or $6$, so that leaves the fourth box to be $6$ or $3$. Therefore, this fraction must be equal to $12/6$, $6/3$ or $12/3$ which is $2$, $2$ or $4$. And since $2=2$, then the fraction is either $2$ or $4$.







    We thus have the equations: $$beginalignBox-Box+2&=18 \ smallrm or quad Box-Box+4&=18.endalign$$ Therefore, $$beginalignBox-Box&=18-2=16 \ smallrm or quad Box-Box&=18-4=12.endalign$$





    And finally,




    From the previous proof, THERE EXISTS NO SOLUTION!




    Proof:




    Now considering the first equation, the first box has to have an option number greater than $16$. The only option number like that is $25$. We thus have $$25-Box=16$$ therefore $Box=25-16=9$. But $9$ is not an option number. That is a contradiction, so the first equation cannot exist. $$requirecancelxcancel Box-Box=16$$







    Considering the second equation, the first box needs to be greater than $12$. It can't be $12$, it has to be greater than $12$. Again, the only option number greater than $12$ is $25$. We thus have $$25-Box=12$$ therefore $Box=25-12=13$. But $13$ is not an option number. That is a contradiction so the second equation cannot exist. $$requirecancelxcancel Box-Box=12$$ But if both equations cannot exist, then...







    ...THERE IS NO SOLUTION!





    Therefore,




    Some lateral-thinking must be required, unless you do not follow by BODMAS or BEDMAS or PEDMAS.







    share|improve this answer














    This answer follows by BODMAS or BEDMAS or PEDMAS.




    Umm...




    THERE IS NO SOLUTION! (without lateral thinking; without inverting the $6$, for example)




    Let's call the numbers we can choose from, the Option Numbers.





    25 cannot be in the third and fourth box.




    Proof:




    This is our equation: $$Box-Box+Box:/:Box=BoxtimesBox.tag$small rm given$$$ $12$, $6$ and $3$ do not divide $25$, so the third box can only be $25$ if the fourth box is $25$. Suppose that involves a solution. Then we have $$Box - Box + 1 = Boxtimes Box.$$







    The largest number for the left hand side is $25-3+1=23$ so the right hand side cannot be greater than $23$. But $23$ is prime and both $22$ and $21$ have two distinct prime factors (although none of option numbers are prime), so the RHS cannot be greater than $20$.

    Also, $20=5times 4 = 10times 2$ which uses none of the option numbers as well, and since $19$ is prime, that means the RHS cannot be greater than $18$. But also, every other product strictly involving the option numbers is greater than $18$, so the RHS cannot be lower than $18$ either.

    If the RHS cannot be greater or lower than $18$, then it is equal to $18$. $$Box-Box+Box:/:Box=18.tag*$(3times 6$ or $6times 3)$$$







    Now $18=6times 3$ which uses two of the option numbers. So now we must find option numbers such that $$Box-Box+1=boxed6times boxed3 =18$$ Therefore $Box-Box=18-1=17$. Of course the first box has to have a bigger value than $17$, because $17$ is positive and all the option numbers are positive. The only option number bigger than $17$ is $25$. Therefore the second box has a value of $25-17=8$ but $8$ is not an option number.

    This is a contradiction, so $25$ cannot be in the third box, and thus fourth one, too.








    $Box:/:Box=2$ or $4$.




    Proof:




    Now $Box:/: Box$ has to be an integer since $18$ is an integer, therefore the numerator box (third one) has an option number greater than the denominator box (fourth one). Since $3$ is the lowest option number, then $3$ cannot be in the third box. That leaves $12$ or $6$, so that leaves the fourth box to be $6$ or $3$. Therefore, this fraction must be equal to $12/6$, $6/3$ or $12/3$ which is $2$, $2$ or $4$. And since $2=2$, then the fraction is either $2$ or $4$.







    We thus have the equations: $$beginalignBox-Box+2&=18 \ smallrm or quad Box-Box+4&=18.endalign$$ Therefore, $$beginalignBox-Box&=18-2=16 \ smallrm or quad Box-Box&=18-4=12.endalign$$





    And finally,




    From the previous proof, THERE EXISTS NO SOLUTION!




    Proof:




    Now considering the first equation, the first box has to have an option number greater than $16$. The only option number like that is $25$. We thus have $$25-Box=16$$ therefore $Box=25-16=9$. But $9$ is not an option number. That is a contradiction, so the first equation cannot exist. $$requirecancelxcancel Box-Box=16$$







    Considering the second equation, the first box needs to be greater than $12$. It can't be $12$, it has to be greater than $12$. Again, the only option number greater than $12$ is $25$. We thus have $$25-Box=12$$ therefore $Box=25-12=13$. But $13$ is not an option number. That is a contradiction so the second equation cannot exist. $$requirecancelxcancel Box-Box=12$$ But if both equations cannot exist, then...







    ...THERE IS NO SOLUTION!





    Therefore,




    Some lateral-thinking must be required, unless you do not follow by BODMAS or BEDMAS or PEDMAS.








    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited 1 hour ago

























    answered 2 hours ago









    user477343

    3,3911745




    3,3911745











    • check the tags in the question :)
      – Oray
      1 hour ago











    • @Oray I did, but DEEM wrote that he/she found a solution without inverting a $6$ to a $9$, and I cannot think of anything else more lateral :P
      – user477343
      1 hour ago











    • @user477343 This is a great answer, and though I hate to do so, I can't help it because it's driving me crazy lol; your OOP is incorrect. PEMDAS is what you're looking for. Multiplication always comes prior to division.
      – PerpetualJ
      13 mins ago

















    • check the tags in the question :)
      – Oray
      1 hour ago











    • @Oray I did, but DEEM wrote that he/she found a solution without inverting a $6$ to a $9$, and I cannot think of anything else more lateral :P
      – user477343
      1 hour ago











    • @user477343 This is a great answer, and though I hate to do so, I can't help it because it's driving me crazy lol; your OOP is incorrect. PEMDAS is what you're looking for. Multiplication always comes prior to division.
      – PerpetualJ
      13 mins ago
















    check the tags in the question :)
    – Oray
    1 hour ago





    check the tags in the question :)
    – Oray
    1 hour ago













    @Oray I did, but DEEM wrote that he/she found a solution without inverting a $6$ to a $9$, and I cannot think of anything else more lateral :P
    – user477343
    1 hour ago





    @Oray I did, but DEEM wrote that he/she found a solution without inverting a $6$ to a $9$, and I cannot think of anything else more lateral :P
    – user477343
    1 hour ago













    @user477343 This is a great answer, and though I hate to do so, I can't help it because it's driving me crazy lol; your OOP is incorrect. PEMDAS is what you're looking for. Multiplication always comes prior to division.
    – PerpetualJ
    13 mins ago





    @user477343 This is a great answer, and though I hate to do so, I can't help it because it's driving me crazy lol; your OOP is incorrect. PEMDAS is what you're looking for. Multiplication always comes prior to division.
    – PerpetualJ
    13 mins ago











    up vote
    1
    down vote













    My solution is




    $25 - 12 + 25 / 3 = 3 times 6$




    because




    the numbers are octal base, and converting to decimal base




    gives




    $21 - 10 + 21 / 3 = 3 times 6$







    share|improve this answer






















    • I have already submitted this answer -.-
      – Oray
      1 hour ago










    • @Oray this is a new, different answer.
      – Weather Vane
      44 mins ago














    up vote
    1
    down vote













    My solution is




    $25 - 12 + 25 / 3 = 3 times 6$




    because




    the numbers are octal base, and converting to decimal base




    gives




    $21 - 10 + 21 / 3 = 3 times 6$







    share|improve this answer






















    • I have already submitted this answer -.-
      – Oray
      1 hour ago










    • @Oray this is a new, different answer.
      – Weather Vane
      44 mins ago












    up vote
    1
    down vote










    up vote
    1
    down vote









    My solution is




    $25 - 12 + 25 / 3 = 3 times 6$




    because




    the numbers are octal base, and converting to decimal base




    gives




    $21 - 10 + 21 / 3 = 3 times 6$







    share|improve this answer














    My solution is




    $25 - 12 + 25 / 3 = 3 times 6$




    because




    the numbers are octal base, and converting to decimal base




    gives




    $21 - 10 + 21 / 3 = 3 times 6$








    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited 34 mins ago

























    answered 1 hour ago









    Weather Vane

    2687




    2687











    • I have already submitted this answer -.-
      – Oray
      1 hour ago










    • @Oray this is a new, different answer.
      – Weather Vane
      44 mins ago
















    • I have already submitted this answer -.-
      – Oray
      1 hour ago










    • @Oray this is a new, different answer.
      – Weather Vane
      44 mins ago















    I have already submitted this answer -.-
    – Oray
    1 hour ago




    I have already submitted this answer -.-
    – Oray
    1 hour ago












    @Oray this is a new, different answer.
    – Weather Vane
    44 mins ago




    @Oray this is a new, different answer.
    – Weather Vane
    44 mins ago










    up vote
    0
    down vote













    Using the tag:




    Each number must be used. It seems like there are 4 numbers: 12, 6, 25, 3. However, I'm guessing there are 6 numbers (lateral thinking): 1, 2, 6, 2, 5, 3. So one of the answers (there may be more with this logic): is

    6 - 5 + 3 / 1 = 2 * 2

    3 - 5 + 6 / 1 = 2 * 2 is another order







    share|improve this answer


























      up vote
      0
      down vote













      Using the tag:




      Each number must be used. It seems like there are 4 numbers: 12, 6, 25, 3. However, I'm guessing there are 6 numbers (lateral thinking): 1, 2, 6, 2, 5, 3. So one of the answers (there may be more with this logic): is

      6 - 5 + 3 / 1 = 2 * 2

      3 - 5 + 6 / 1 = 2 * 2 is another order







      share|improve this answer
























        up vote
        0
        down vote










        up vote
        0
        down vote









        Using the tag:




        Each number must be used. It seems like there are 4 numbers: 12, 6, 25, 3. However, I'm guessing there are 6 numbers (lateral thinking): 1, 2, 6, 2, 5, 3. So one of the answers (there may be more with this logic): is

        6 - 5 + 3 / 1 = 2 * 2

        3 - 5 + 6 / 1 = 2 * 2 is another order







        share|improve this answer














        Using the tag:




        Each number must be used. It seems like there are 4 numbers: 12, 6, 25, 3. However, I'm guessing there are 6 numbers (lateral thinking): 1, 2, 6, 2, 5, 3. So one of the answers (there may be more with this logic): is

        6 - 5 + 3 / 1 = 2 * 2

        3 - 5 + 6 / 1 = 2 * 2 is another order








        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited 39 mins ago

























        answered 1 hour ago









        Greg

        61118




        61118




















            up vote
            0
            down vote













            There doesn't seem to be anything that says that only one number can be placed into each box. Thus




            $$12 - 25 + 66 div 3 = 3 times 3$$




            would be a valid solution.



            It just requires putting




            two $6$s in the same box.







            share|improve this answer




















            • @Gareth I just saw your comment on the question above, after posting this solution. I'm surprised you didn't post an answer yourself!
              – GentlePurpleRain♦
              14 mins ago










            • OP responded "No more than one number in the square please"
              – Greg
              5 mins ago










            • @Greg: I'm only putting one number in each; I'm just putting one number twice in one of them... :P (This is a valid answer to the question as posed. That criterion was not in the question.)
              – GentlePurpleRain♦
              12 secs ago














            up vote
            0
            down vote













            There doesn't seem to be anything that says that only one number can be placed into each box. Thus




            $$12 - 25 + 66 div 3 = 3 times 3$$




            would be a valid solution.



            It just requires putting




            two $6$s in the same box.







            share|improve this answer




















            • @Gareth I just saw your comment on the question above, after posting this solution. I'm surprised you didn't post an answer yourself!
              – GentlePurpleRain♦
              14 mins ago










            • OP responded "No more than one number in the square please"
              – Greg
              5 mins ago










            • @Greg: I'm only putting one number in each; I'm just putting one number twice in one of them... :P (This is a valid answer to the question as posed. That criterion was not in the question.)
              – GentlePurpleRain♦
              12 secs ago












            up vote
            0
            down vote










            up vote
            0
            down vote









            There doesn't seem to be anything that says that only one number can be placed into each box. Thus




            $$12 - 25 + 66 div 3 = 3 times 3$$




            would be a valid solution.



            It just requires putting




            two $6$s in the same box.







            share|improve this answer












            There doesn't seem to be anything that says that only one number can be placed into each box. Thus




            $$12 - 25 + 66 div 3 = 3 times 3$$




            would be a valid solution.



            It just requires putting




            two $6$s in the same box.








            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered 17 mins ago









            GentlePurpleRain♦

            16k565132




            16k565132











            • @Gareth I just saw your comment on the question above, after posting this solution. I'm surprised you didn't post an answer yourself!
              – GentlePurpleRain♦
              14 mins ago










            • OP responded "No more than one number in the square please"
              – Greg
              5 mins ago










            • @Greg: I'm only putting one number in each; I'm just putting one number twice in one of them... :P (This is a valid answer to the question as posed. That criterion was not in the question.)
              – GentlePurpleRain♦
              12 secs ago
















            • @Gareth I just saw your comment on the question above, after posting this solution. I'm surprised you didn't post an answer yourself!
              – GentlePurpleRain♦
              14 mins ago










            • OP responded "No more than one number in the square please"
              – Greg
              5 mins ago










            • @Greg: I'm only putting one number in each; I'm just putting one number twice in one of them... :P (This is a valid answer to the question as posed. That criterion was not in the question.)
              – GentlePurpleRain♦
              12 secs ago















            @Gareth I just saw your comment on the question above, after posting this solution. I'm surprised you didn't post an answer yourself!
            – GentlePurpleRain♦
            14 mins ago




            @Gareth I just saw your comment on the question above, after posting this solution. I'm surprised you didn't post an answer yourself!
            – GentlePurpleRain♦
            14 mins ago












            OP responded "No more than one number in the square please"
            – Greg
            5 mins ago




            OP responded "No more than one number in the square please"
            – Greg
            5 mins ago












            @Greg: I'm only putting one number in each; I'm just putting one number twice in one of them... :P (This is a valid answer to the question as posed. That criterion was not in the question.)
            – GentlePurpleRain♦
            12 secs ago




            @Greg: I'm only putting one number in each; I'm just putting one number twice in one of them... :P (This is a valid answer to the question as posed. That criterion was not in the question.)
            – GentlePurpleRain♦
            12 secs ago

















             

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