Write down the solution for this math problem: Solve 25439 = 1819*f + 58181 for f.
answer: -18

Write down the solution for this math problem: Solve 0 = 267*f - 255*f - 72 for f.
answer: 6

Write down the solution for this math problem: Solve 150 = 115*a - 65*a for a.
answer: 3

Write down the solution for this math problem: Solve -78691 = -1841*f - 17630 + 7751 + 21397 for f.
answer:
49