a store has a sale for 20% off. You decided to buy a $15 t-shirts.

(a) How much money will you save

(b) How much money will you spend on the t-shirt?

(a) To calculate the amount saved, we need to find 20% of the original price.

20% of $15 = $15 * 0.20 = $3

Therefore, you will save $3 by purchasing the t-shirt on sale.

(b) To calculate the amount spent on the t-shirt after the discount, we need to subtract the amount saved from the original price.

Amount spent = Original price - Amount saved
Amount spent = $15 - $3 = $12

Therefore, you will spend $12 on the t-shirt after the discount.