Question

Additon 1,3,5,7,9,11,15= 30 _+_+_+_+_=30

Answer 1

Gaurav Agrawal answered last year in UPSC very intelligently and using his imagination.
       as 3! + 3! + 3! + 3! + 3! = 30

This question is asked so many times.  We can answer this question in many ways using the factorial function.

 3! + 1 + 3 + 9 + 11          = 30
        1 + 5 + 7 + 3! + 11               = 30
              3! + 3! + 3! + 11 + 1             = 30
                  3! + 3! + 11 + 5 + 1               = 30
             11+ 1 + 1 + 3! + 11              = 30
        15 + 3 + 3 + 3 + 3!              = 30
      13 + 1 + 1 + 9 + 3!            = 30
          13 + 1 + 3 + 7 + 3!            = 30
                13 + 5 + 3 + 3 + 3!            = 30

perhaps there are more ways.  We actually need a function or operator which converts an odd integer in to an even integer.  Factorial is one such function. If there are other functions, we can use those also.

Answer 2

13+5+3+3+3!=30............................