If 25 dimes were moved from Box A to box B there would be an equal number of dimes in both boxes. If 100 dimes were moved from Box B to Box A, the ratio of dimes in box A to box B would be 7:2. What was the original number of dimes in Box A?

Answer 1

A - 25 = B + 25
... A - 50 = B

7(B - 100) = 2(A + 100)
... 7 B - 700 = 2 A + 200
... 7 B = 2 A + 900

substituting
... 7(A - 50) = 2 A + 900
... 7 A - 350 = 2 A + 900
... 5 A = 1250 ... A = 250