Final answer:
The group of friends needs 20 gallons of gas to drive the remaining 380 miles without stopping, based on their car's fuel efficiency of 19 miles per gallon.
Step-by-step explanation:
The question asks us to calculate the amount of gasoline a group of friends needs to drive an additional 380 miles without stopping to refuel, given that they previously traveled 228 miles on 12 gallons of gas.
To solve this, we first find the car's miles-per-gallon (mpg) by dividing the distance traveled by the amount of gas used:
mpg = 228 miles / 12 gallons = 19 miles/gallon
Next, we calculate how many gallons are needed for the remaining 380 miles:
gallons needed = 380 miles / 19 miles/gallon
gallons needed = 20 gallons
Therefore, the group of friends needs to refuel with 20 gallons of gas to reach their destination without stopping again.