Question

_+_+_+_+_=30
Use 1,3,5,7,9,11,13,15
You can repeat the nos

Answer 1

we cant get even solution if we add odd no. we atleast want 1 even no.

Answer 2

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! +1 + 5 + 7 +11 = 30
Similarly you can find many such answers.

Hope that helps !!