QUESTION: Math problem: Solve -538*c + 24 = -530*c for c.
ANS: 3
QUESTION: Math problem: Solve d = -42*d + 86 for d.
ANS: 2
QUESTION: Math problem: Solve -1303*f + 660 = -1333*f for f.
ANS: -22
QUESTION: Math problem: Solve -1438*r + 1407*r - 1 - 650 = 0 for r.
ANS:
-21