The factors of 21 that add up to 8 are 1 and 7.
268
2
-1005
167
The factors of 8 are 1, 2, 4, and 8. The factors that add up to 10 are 2 and 8.
Factors of 250 that add up to 8 = 1 + 2 + 5
212
1012
1510
47
15 and 4 are the factors of 120 that add up to 19.