Question
A boy cycles to his school at 40 km/h and comes back at
30 km/h. If the total time for going and coming back is 210 minutes, find the distance between his home and school.Solution
ATQ, Let the required distance be 'D' km. So, (D/40) + (D/30) = (210/60) Or, (7D/120) = (210/60) Or, 'D' = 42 × 2 = 84 km
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