Mr. Jones drove from Town A to Town B in x hours. On the return trip

Question

Mr. Jones drove from Town A to Town B in x hours. On the return trip over the same route, his average speed was twice as fast. Which of the following expresses the total number of driving hours for the round trip?

(A) (2/3)x
(B) (3/2)x
(C) (5/3)x
(D) 2x
(E) 3x

(A) (2/3)x
(B) (3/2)x
(C) (5/3)x
(D) 2x
(E) 3x

adil123 · Answer

Answer - b
from a to b 
t = x hrs (assume)
speed = y (assume)
 speed is inversley prop. to time
So, y =k/x ( k is constant)
k= xy

From b to a 
s= 2y 
speed is inversely prop to time
so, 2y=k/t ( k is constant)
 hence t =x/2

total time = x+x/2=3x/2

ehsan090 · Answer

During up trip he consumed X hour
During return since his speed was twice this mean he consumed half time as compared to up trip so it will be X/2
now sum the total trip
Total=X+X/2
3X/2
Option:B

Skywalker18 · Answer

Let the distance between town A and B is 100 km 
Let average speed from A to B SpeedAB = 50 km/h 
Time taken for Jones to drive from town A to B , x = 100/50 = 2 hours

On the return trip from B to A over the same route , his average spped = 100km/h
Time taken for Jones to drive from town B to A = 100/100 = 1 hour
Total time taken = 3 hours

Now testing using answer options 
(A) (2/3)x = 2/3 * 2 = 4/3 Not equal to 3
(B) (3/2)x = (3/2)*2 = 3 Correct
(C) (5/3)x = 10/3 - Not equal to 3
(D) 2x = 4 - Not equal to 3
(E) 3x = 6 -Not equal to 3

Answer B

gracie · Answer

twice the speed=half the time returning
x+(1/2)x=(3/2)x
B

ScottTargetTestPrep · Answer

We are given that his driving time from Town A to Town B is x hours, and on his return trip, his average speed was twice as fast. Because of that, his driving time for his return trip from Town B to Town A will require half as much time, or x/2 hours. Thus, his total driving time is x + x/2 = 3x/2 hours.

Answer: B

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Mr. Jones drove from Town A to Town B in x hours. On the return trip

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