Question

. If a boy walks to his school at a speed of 4 km/hr, he reaches the school 10 minutes before
school time. If he walks at 3 km/hr, he reaches the school 10 minutes late. Find the distance
between his house and the school ​

Answer 1

Answer:

Let the distance be x km

Difference in timing=20 min=31 hr

∴3x−4x=31

⇒4x−3x=4

⇒x=4 km

Answer 2

Answer:

distance is 4km

explanation...

1. let usual time taken be t then time taken when he walks at the speed of 4km/hr is t-1/6hr
2. and time taken when he walks at the speed of 3km/hr is t+1/6hr
3. let distance be xkm
4. in first case

x=4×(t-1/6)

in second case x=3(t+1/6)

on comparing both equations we get

t=7/6

and put the value of t in any of yhe above eq we get

x=4km