Jerry and Tom had $720 altogether. Jerry gave 20% of his money to Tom. Tom then gave 25% of his money back to Jerry. In the end both boys had an equal amount of money each. How much money did each boy had at first?

Answer 1

Let's say Jerry had x dollars at first.

After giving 20% of his money to Tom, Jerry remained with 0.8*x dollars.
Tom received 0.2*x dollars.
Together, Jerry and Tom had (0.8*x + 0.2*x) = 0.8*x + 0.2*x = 1*x = x + 0.2*x + 0.8*x = 1*x = 720 dollars
Tom therefore had 0.2*x = 0.2*720 = 144 dollars
Since both boys had the same amount of money in the end, Jerry had 0.8*x = 0.8*720 = 576 dollars at first. Answer: \boxed{576}.