Question

Juliet drove from point A to point B at an average speed of 50 kmph and returned to point A along
the same route at average speed of 46 kmph. If her total driving time for the journey was 4 hours,
how many minutes did it take Juliet to drive from point B to point A?
A) 115 minutes
B) 120 minutes
C) 125 minutes
D) 130 minutes

Answer 1

Answer:

Option C is correct.i.e., 125 minutes

Step-by-step explanation:

Given: Average Speed from point A to point B = 50 kmph

           Average Speed from point B to point A = 46 kmph

           Total time taken from A to B then B to A = 4 hrs

To find: No of minutes from point B to point A

Let D be the Distance from point A to B and same from point B to point A

Time taken from point A to point B, $T_1=\frac{D}{50}\:hr$

Time taken from point B to point A, $T_2=\frac{D}{46}\:hr$

According to the question,

$T_1+T_2=4$

$\frac{D}{50}+\frac{D}{46}=4$

46D + 50D = 4 × 50 × 46

96D = 9200

$D=\frac{9200}{96}$

$D=\frac{575}{6}\:km$

Time taken from point B to point A = $\frac{\frac{575}{6}}{46}$

                                                           = $\frac{575}{46\times6}$

                                                           = $\frac{575}{46\times6}\times60$

                                                           = 125 minutes

Therefore, Option C is correct.i.e., 125 minutes