Question

____ + ____+ ____ = 30?

Use only 1,3,5,7,9,11,13,15 these numbers and you can repeat the numbers

Answer 1

it is it is impossible to get answer in even number by adding odd number. 
But it can do by factorial method.
3! + 15 + 9 =30
3! + 11 + 13 = 30 
3! = 1*2*3 = 6

Answer 2

3! +15+9 =30 
or u can also write
3!+11+13=30
in this way u can write in ways using factorial
we should use factorial here because adding odd numbers cant give even ok.