Zoe uses 1/3 of her money to buy a dress and 1/4 of the remaining
amount to buy some magazines. After that, she uses 2/5 of the rest
of the money to buy a present.
If she has $54 left, how much money did she spend on the magazines?
x - (x/3 + x/6 + x/5) = 54
x = 180
She spent on the magazines $30.
Set Zoe have x altogether,
Money for clothes : 1/3x
Money for magazines : (x - 1/3x) * 1/4
Money for gifts : (x - 1/3x - 1/6x) * 2/5 = 1/5x
x - 1/3x - 1/6x - 1/5x = 54
3/10x = 54 x = 180
Money for magazines = 1/6x = 180 * 1/6