If Owen gives $50 to charley, they will have an equal amount of money. If Charley gives $100 to Owen, the ratio of Owen's money to Charley's money will be 4:1. How much money does Owen have in the beginning?
If Owen has x and Charley has y, then we are told that
x-50 = y+50
(x+100) = 4(y-100)
Now just find x.