Can anyone tell me how to approach the following style question:
Use three of the numbers on the left once only to make up the number you are given.
7,9,11,13,16 : 31= ( + + )
I have not come across this type of question before, but I would suggest that you take one number away from the 31 and then see if the remainder can be made by two of the other numbers.
eg, 31-7 = 24, can 24 be made by two others?
31- 9= 22, can 22 be made by two others?
31- 11= 20, can 20 be made by two others? 7+13 = 20
so the answer is 7+13+11 (I think!)