Explanation:
x
x+2
x+4
x+6
x+8
these are the 5 consecutive odd integers.
when starting with an odd number as x, with every added 2 we get again an odd number.
the sum of the last 3 integers is 3 more than the sum of the 2 greatest :
x+4 + x+6 + x+8 = x+6 + x+8 + 3
we can subtract (x+6) abd (x+8) from both sides :
x + 4 = 3
x = -1
so, the 5 numbers are
-1
1
3
5
7
3 + 5 + 7 = 15
5 + 7 + 3 = 15
correct.