sum must be 24

Question

Using these numbers my answer has to equal 24. Need to add, subtract , divide, or multiply with the numbers 1,4,5,12 but the answer must be 24. Must use all four numbers and can only use each number once.

Answer 1

There is some strategy in this problem.  The rules say,

   "Must use all four numbers and can only use each number once"

   "Need to add, subtract , divide, or multiply"

   "Using ... 1,4,5,12 ...answer has to equal 24"

 

So, if you need any other numbers to use during the computation (as intermediate numbers), then you must create them also.  What numbers would be useful?  If the answer must be 24, then having a 2 to multiply by the 12 is nice.  Or a 3 to multiply by the 4 before adding to the 12.  See how you can use intermediate numbers?

 

Well, if you want to make a 2 to multiply by the 12 using 1,4,5, how do you do it?

 

With a good list of the numbers you need as intermediates, the possibilities get fewer and fewer very fast.  Then, you have the solution !