1. If they washed 12 cars in 3 hours you need to find out the rate of how many cars they washed per hour
12/3=4
They wash 4 cars per hour
In 8 hours they would have washed 32 cars
If they charge $5 per car then 32*5= 160
They would have earned $160 after 8 hours.
2. It's $48 for 12 packages
How many times does 12 go into 180?
180/12=15
So if you have to buy 15 of 12 packages then you would multiply 15*48
15*48= 720
It would be $720 for 180 packages.