Question
A boy cycles from his school to home. Cycling at 12
km/h, he gets home 25 minutes late. But with a speed of (30/6) m/s, he reaches only 10 minutes late. What’s the distance between his school and home?Solution
ATQ,
Let distance = x km
T1 = x/12
Speed = (30/6) × (18/5) = 18 km/h
T2 = x/18
Difference = 25 - 10 = 15 minutes = 1/4 hour
(x/12) - (x/18) = 1/4
LCM = 36
(3x - 2x)/36 = 1/4 → x/36 = 1/4 → x = 9
Answer: 9 km
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