Estimate the number of gallons of gasoline consumed by the total of all automobile drivers in the u. s., per year. suppose that there are about 3 × 10^8 people in the united states, approximately half of the them have cars, each car drives an average of 12,000 mi per year, and consumes a gallon of gasoline for each 20 mi?

Explanation:

Total number of people in US is  

Only half of them have cars. So, Number of cars in US

Each cars drives 12000 miles, so total distance travelled by all of these cars combined

To travel 20 miles, we need 1 gallon of gasoline

Amount of gasoline required to travel one mile is   gallons

Amount of gasoline required to cover the distance 'D'.

Amount of gasoline required to cover the distance 'D'.

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