Question
A boy goes to tuition at (5/7) of his normal walking
speed and reaches 24 minutes late. Find his usual time to reach the tuition centre.Solution
ATQ, When distance is constant, Time ∝ (1 / Speed) So, the ratio of usual time to new time = 5 : 7 Let the usual time = 5t minutes and the new time = 7t minutes. 7t – 5t = 24 ⇒ 2t = 24 ⇒ t = 12 Usual time = 5t = 5 × 12 = 60 minutes
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