Jay and Jack had the same amount of money at first. Jay gave $35 to his brother. Jack's mother gave him another $25. The amount of money Jack had in the end was four times as much as the amount of money Jay had. How much money did each of them have at first?
let x be Jay’s original money
let y be Jack’s original money
x = y
Jay gave $35 to his brother
x - 35
Jack’s mother gave him $25
y + 25
The amount of money they had in the end is given by
y + 25 = 4(x - 35)
Since x = y,
x + 25 = 4(x - 35)
x + 25 = 4x - 140
x - 4x = -140 - 25
-3x/-3 = -165/-3
x = 55
$55