The discount is 15% which we can write as 0.15 and we multiply that by 30 to get the discount, which is $4.50. We subtract that from the original price; 30 to get $25.50 as the sale price. We want to find out what percent of 30 25.50 is, so we divide 25.50 and 30 to get 0.85. Multiply that by 100 to get 85%.
