Sharif and his sister have the same amount of money. After Sharif spent $75 and his sister spent $37, his sister had three times as much money as sharif. How much money did sharif have at first?
Sharif and his sister have the same amount of money: Each has x.
After Sharif spent 75, Sharif now has x - 75
After his sister spent 37, his sister now has x - 37
His sister has three times as much money as Sharif: x - 37 = 3(x - 75)
x - 37 = 3x - 225
x - 37 + 225 = 3x - 225 + 225
x + 188 = 3x
x + 188 - x = 3x - x
188 = 2x
188 / 2 = 2x / 2
94 = x
Sharif started with 94.