Question

A man travelled a distance of 61 miles in 7 hours. He covered a part of the distance at a
speed of 8 miles/ hr and the remaining at a speed of 10 miles/ hr. How long did he travel at 8
miles/ hr?

Answer 1

Solution:

Let us understand how we can calculate it-

Let the time in which he travelled on foot=x hr

Then the time in which he travelled on bicycle

=(9−x)=(9−x)hr

distance = speed × time

⇒4x+9(9−x)=61

⇒4x+81−9x=61

⇒5x=20

x=4

⇒4x+9(9−x)=61⇒4x+81−9x=61⇒5x=20⇒x=4

Distance traveled on foot

=4x

=4×4=16 km

=4x=4×4=16 km

Answer 2

Step-by-step explanation:

Let the time in which he travelled on foot = x hour

Time for travelling on bicycle = (9 - x) hr

Distance = Speed * Time, and Total distance = 61 km

So,

4x + 9(9-x) = 61

=> 5x = 20

=> x = 4

So distance traveled on foot = 4(4) = 16 km