Question

Without any stoppage a person travels a certain distance at an average speed of 42 km/hr, and with stoppages he covers the same distance at an average speed of 28 km/hr. How many minutes per hour does he stop ?

• A. $14$ minutes
• B. $15$ minutes
• C. $28$ minutes
• D. $20$ minutes

Answer 1

Answer: (D)

$20$ minutes

Given that,

Without any stoppage a person travels a certain distance at an average speed $v=42km/hr$

With any stoppage a person travels a certain distance at an average speed $v=28km/hr$

We know that,

Difference in distance traveled in one hour

$D=41-28=14km$

Which is lost due to stoppages.

So, Stoppages time is

$t=\frac{14}{42}hr$

Time in minutes is

$t=\frac{14}{42}\times 60$

$t=20min$

He stop in $20min$.

Hence, Option D is correct