Question

An advertisement claims that a 5-pound box of detergent will wash 20 loads of laundry. A 5-pound box costs $3.50. A 15-pound box costs $10.00. How much will you save PER LOAD if you buy the 15-pound box? (Round all answers to the nearest tenth of a cent.)

Answer 1

Well, you get 60 loads for $10 and 20 loads for $3.50. How many 5's does it take to get to 15? You're right, 3. So, if you wanted to get 3 - 5 lb boxes, it would wash the the same amount of loads as the $10 15 lb box. So, what you're going to do is take $3.50 x 3 because that's how many you would need to get the same amount as the 15 lb box. you get the product of $10.50 when you multiply the 3.50 box times 3. Therefore, by buying the 15 lb box, you're saving $.50.