SOLUTION: 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 d

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Question 1144880: 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
Is B correct?
The question and the answer choices in the link here: https://prnt.sc/p4af9h
Answer by ikleyn(52788) (Show Source):
You can put this solution on YOUR website!
.

Let x be the TOTAL number of vehicles (the value under the question). Then you have this equation 0.8x*13.5 + 0.2x*20 + 3x - 3 = 5*5280 Its both sides express the length of the traffic jam in feet, by the OBVIOUS way. From the equation x = = 1483.315 (approximately). Since we estimate to get the integer number, round it to the nearest integer. ANSWER. 1483 vehicles.