He drove 14 miles per gallon.
Step-by-step explanation:
Total distance = 278.2 miles
Gasoline used = 19.6 gallons
We need to find the unit rate of gallon, therefore, we will divide the total distance covered with the gasoline used to find the distance drove with 1 gallon of gasoline.
Distance per gallon = 
Distance per gallon = 
Distance per gallon = 
Rounding of to nearest whole amount;
Distance per gallon = 14 miles
He drove 14 miles per gallon.
Keywords: distance, unit rate
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