Question

_ _ _=30 [1,3,5,7,9,11,13,15]

Answer 1

Odd numbers don't add up to give you an even number.
It is possible only in case of factorial.

3!+1+3+13+7=30 

3!+3!+3!+3!+3!=30

11+1+3+15=30

3! + 15 + 9 = 30

Answer 2

As we would never get the sum of 30 by adding odd numbers.

So , we have to use Factorial Method.

There can be many answers by using factorial Method , the following is one of them. - - 
⇒ 3 ! + 11 + 13 = 30