20. A backpack that normally sells for $39 is on sale for 33% off. Find the
amount of the discount and the sale price.
21. In August, the Simons' water bill was $48. In September, it was 15%
lower. What was the Simons' water bill in September?
22. A gallery owner purchased a very old painting for $3,000. The painting
sells at a 325% increase in price. What is the retail price of the
painting?
