Your question is Form Printing Rate Math. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
One printer prints 1/4 of 500 copies of forms but the other prints 3/7ths faster; how many pages can you print from each machine so that they print the same number of pages x20 minus 8 and divided by -17?