3/5 of John’s savings is equal to 2/3 of Mark’s savings. The difference in their savings is equal to 1/5 of Bill’s savings. If John saves $35 more than Bill, how much must Mark give to Bill so that both of them have the same amount of money?
(3/5)j = 2/3(m)
j - m = (1/5)b
j = b + 35
Now this is just a three-variable system of equations. You should be able to use system of equations to solve this, and then figure out how much Mark has to give to Bill.