The answer is 17/25
Because you would need to find the lowest comon denominator between them which is the 25.
so 2/5 would equal 2^5/5^5 which equals 10/25
so then you would say 10/25 + 2/25 + 4//25
so that is 10 + 2 + 4/25
10 +2 is 12 then 12 + 4 is 17
So it would be 17/25