Math CentralQuandaries & Queries


Question from sharon, a parent:

We have been battling with this for days and cant find any solution -

Using each of the following numbers once, fill all the spaces in the triangles so that each side of the triangle adds up to 57

numbers are 11,12,13,14,15,16,17,18,19

diagram is -

    0   0    
  0   57   0  
0   0   0   0


Any ideas ? this has to be in in just over 24 hrs!


You should first fill in the three corners. Note that the sum of the three side totals will equal 3 times 57, which is 171. What is the sum of the given nine numbers? How much more do you need from the three corners (which each appears twice in forming the grand total of 171) to reach 171? Which three numbers in the given list sum to that missing quantity?


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