The sum of 19 and 9 is 28.
The sum of 8, 11 and 9 is 28.
The prime factors of 28 are 2 and 7. Their sum is 9.
9*n + 28 >= -20.
(2 x 9) + (3 x 9) = 5 x 9 = 45
4x(7+9)= 28+36=64.
28 + 35 = (4 x 7) + (5 x 7) = 9 x 7 = 63
3 and 6
The sum is 28+38 = 66
The sum of 2/5 and 2/9 is 28/45.
It is 28, of course!
sum=360