A boy walking at a speed of 15 km/h reaches his school 20 min late. Next time he increases his speed by 5 km/h but still he late by 5 min. Find the distance of the school from his home.?
Correct Answer: 15 km
Explanation:
Let the distance = x
Here, the difference in time
= 20 - 5 = 15 min
= 15/60 = 1/4h
Speed during next journey
= 15 + 5 = 20 km/h
According to the question,
x/15 - x/20 = 1/4
⇒ 4x - 3x/60 = 1/4
⇒ x = 60/4 = 15
∴ x = 15 km
