Lori wants to go to the beach on saturday but she's not sure if she has enough gas in her car to drive there and back home. The beach is 77 miles from Lori's house but the car gets about 28 miles per gallon. How many gallons of gas does Lori need to have in her car to make the trip to the beach?

To make the trip there and back home, it's 77 miles x 2, so total Lori is going to have to drive 154 miles. To find out how many gallons she'll need, divide 154 miles by 28 mpg. Soooo she'll need 5.5 gallons EXACTLY to make the roundtrip.