Question

On a residential single lane road there was a wreck that backed up traffic for 5 miles. 80% of the traffic consists of cars and 20% of the traffic consists of trucks. The average distance between vehicles is 3 feet. The average length of a car is 13.5 feet and the average length of a truck is 20 feet. Estimate how many vehicles are stuck in the traffic jam. (Hint: There are 5280 feet in 1 mile.) A. 853 vehicles B. 1510 vehicles C. 2103 vehicles D. 2320 vehicles

Answer 1

Answer: b) 1510 vehicles

Explanation:

Total: 5 miles x 5280 ft per mile = 26,400

Cars: 80% of vehicles are cars with a length of 13.5 = 0.8(13.5)v = 10.8v

Trucks: 20% of vehicles are trucks with length of 20 = 0.2(20)v = 4v

Between: Distance between two vehicles is 3: (3/2)v = 1.5v

Total = Cars + Trucks + Between

26,400 = 10.8v + 4v + 1.5v

26,400 = 16.3v

1619.6 = v

the closest number of all of the options is (b) 1510