Question

Can we get 30 by adding 3 odd numbers within 15 3 times?

Answer 1

There can be many answers but the basic idea is using factorial. Factorial is the product of all the numbers from 1 to that number. For example 4! = 1 x 2 x 3 x 4 = 24.
 
So, 3! + 11 + 13 = 30
Similarly you can find many such answers.

Hope that helps !!

Answer 2

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

3! + 15 + 9 = 30