Answer:
If you were trying to find 15% of 18, that would be multiplying a decimal, but, you need to mutliply a whole number. $120 should be your answer. People, correct me if I'm wrong (seriously though, not 100% sure if this is correct).
Explanation:
18 = 15% x Y
18 = 15/100 x Y
Y = 18 × 100/15
Y = 18 × 100 ÷ 15
Y = 120