The regular price is $18. The book is discounted, and then put on a sales tax. To find the discounted price, multiply 18 by 0.15, and this will give you 15% of 18. Then subtract 18 by that number.
18 x .015 = 2.70
18 - 2.70 = 15.30
The book's price when you add the discount is $15.30. She needs to pay a 6% sales tax on the discounted price. We need to find 6% of $15.30 so we multiply again. The only difference is that instrad of subtracting after, we add because the sales tax is what Ellen has to PAY so the amount INCREASES.
15.30 x 0.06 = 0.918
15.30 + 0.918 = 16.218
Round to the nearest hundreth, since we're dealing with money.
Answer: $16.22
:)
