You need to select three numbers (no more, no less), from a list to add up to thirty. here’s the list of numbers (you can use them more than once): 1, 3, 5, 7, 9, 11, 13, 15.

The answer is: 1&9 + 11 = 30

Why?

Well, there is actually no real solution to this problem, since this question is asking us to add up 3 numbers so that the sum is 30.

That is impossible. Adding three odd numbers can only result in another odd number. An odd number is just an even number + 1. So adding three odd numbers is simply adding 3 even numbers + 3 1s. 3 even numbers would equal an even number, + 3 would turn it into an odd number.

The question is asking us to add up three numbers from a list, which only includes odd numbers, so that the sum is 30, an even number, therefore there is no possible solution.

A loophole to this question is to 'combine' 2 numbers from the list, in this case, 1 and 9, and add them up with another number, 11. 19 + 11 = 30. Three numbers were used and they were from the list provided.

Using this method, here are all possible solutions:

1&5 + 15
1&7 + 13
1&9 + 11
15 + 1&5
13 + 1&7
11 + 1&9