A car starts from X and moves towards Y.

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A car starts from X and moves towards Y.

by VJesus12 » Thu Nov 16, 2017 7:26 am
A car starts from X and moves towards Y. At the same time another car starts from Y and moves towards X. Both travel at a constant speed and meet after 4 hours. During that time, the faster car traveled 2/3 of the distance XY. How long would it take the slower car to travel the distance XY?

A 6 hours
B. 8 hours
C. 10 hours
D. 12 hours
E. 15 hours

The OA is D .

Experts, is there a simple way to solve this PS question? I need your help.

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by GMATGuruNY » Thu Nov 16, 2017 7:41 am
VJesus12 wrote:A car starts from X and moves towards Y. At the same time another car starts from Y and moves towards X. Both travel at a constant speed and meet after 4 hours. During that time, the faster car traveled 2/3 of the distance XY. How long would it take the slower car to travel the distance XY?

A 6 hours
B. 8 hours
C. 10 hours
D. 12 hours
E. 15 hours
Let the distance between X and Y = 12 miles.
Since the distance traveled by the faster car in 4 hours = (2/3)(12) = 8 miles, the distance traveled by the slower car in 4 hours = (total distance) - (distance traveled by the faster car) = 12-8 = 4 miles.
Since the slower car travels 4 miles in 4 hours, the rate for the slower car = d/t = 4/4 = 1 mile per hour.
Since the rate for the slower car = 1 mile per hour, the time for the slower car to travel the entire 12 miles = d/r = 12/1 = 12 hours.

The correct answer is D.
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by EconomistGMATTutor » Thu Nov 16, 2017 8:19 am
Hello Vjesus12.

Let's see:

If it took to car B 4 hours to travel 1/3 of the distance, then it will take 8 hours to travel (2/3) of the distance. So, it takes 12 hours (4 hours 1/3, 8 hours 2/3) to travel form X to Y.

I hope this explanation may help you.

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by Scott@TargetTestPrep » Wed Oct 16, 2019 6:08 pm
VJesus12 wrote:A car starts from X and moves towards Y. At the same time another car starts from Y and moves towards X. Both travel at a constant speed and meet after 4 hours. During that time, the faster car traveled 2/3 of the distance XY. How long would it take the slower car to travel the distance XY?

A 6 hours
B. 8 hours
C. 10 hours
D. 12 hours
E. 15 hours

The OA is D .

Experts, is there a simple way to solve this PS question? I need your help.
We can let the total distance = 240 miles. So the faster car traveled 2/3 x 240 = 160 miles, and thus the slower car traveled 240 - 160 = 80 miles. Since the two cars meet after 4 hours, it must be the case that the slower car traveled 80 miles in 4 hours, which means the speed of the slower car is 80/4 = 20 miles per hour. Therefore, it would take the slower car 240/20 = 12 hours to travel the entire distance XY.

Answer: D

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