Question

_+_+_=30
you can use only(1;3,5,7,9,11,13,15)

u can also repeat the number

Answer 1

The above condition with the given set of numbers is not possible. Because, when we add any two odd numbers, the resultant number is always an even number. Hence, even if we repeat a single number again, the solution cannot be obtained.

Answer 2

It is not possible to get a sum 30 by using the numbers given here as they all are odd therefore if we take 3 odd numbers and do there sum it will never be 30.
for example :- 13+15+1=29
                      11+11+7=29
                      3+9+15=27
                      11+13+7=31
therefore the sum can never be 30 as it is an even number