The Gifted and Talented Maths Club from Years 5 & 6 found these solutions:
8, 7, 13, 10, 6, 12, 9
6, 9, 11, 12, 4, 14, 7
Michelle said: First of all we need to find all the pairs that add up to 15.
Jodie and Murat said: We should chose the numbers that are close together to start with so we will use 7 and 8. They are in the middle of the numbers that we have (they are the closest to half of 15)so that when we want to make the other totals we will have a variety of big and small numbers to make them.
Murat and Jodie found our first solution.
Monel said: I will try the next two numbers that are closest together.
Monel found our second solution.
Then Murat noticed something interesting. The numbers in the first and second solutions have a difference of two. For example, the first numbers are 8 and 6 which have a difference of 2 and the second numbers are 7 and 9 which have a difference of 2 and so on.