Question

A student walks from his house at 4 km/hr and reaches his school 5 minutes late.if He reaches 15 minutes early
. What is the distance of his school fom his house​

Answer 1

Answer:

Let us say that the actual distance between Ram's house and school is 'd' km and the ideal time to cover the distance is 't' hours.

When he walks at 5 kmph, he reaches 5 minutes (or 1/12 hours) early

=> d/5 = t - 1/12

=> t = d/5 + 1/12

When he walks at 4 kmph, he reaches 5 minutes (or 1/12 hours) late

=> d/4 = t + 1/12

=> t = d/4 - 1/12

Using the above equations, we can say

d/5 + 1/12 = d/4 - 1/12

=> d/4 - d/5 = 1/12 + 1/12

=> d/20 = 1/6

=> d = 20/6 = 3.33 km