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

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
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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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