Giovanni buys a sweater at a store. The normal price is $30 but the sweater is on sale for 25% off.
a) How much in dollars will Giovanni save from the sale?
b) What is the sale price of the sweater?
c) The next week, Giovanni goes back to the same store and sees the same sweater. Now it’s on sale for $18. What is the percent decrease from the original $30 price to the new $18 price?