Question

_+_+_+_+_=30 Fill the boxes using (1, 3, 5, 7, 9, 11, 13, 15) U can also repeat the numbers..?

Answer 1

By using the factorial sign ! 

3 + 5 + 7 + 9 + 3! = 30

3! means that = 1*2*3
                      = 6

So we concluded that 

3 + 5 + 7 + 9 + 6 = 30

Answer 2

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

Note that 3!=3*2*1=6