Question
If a car runs at 40 km/hr, it reaches its destination
late by 12 minutes but if runs at 48 km/hr it is late by 8 minutes. What is the correct time for the journey?Solution
Distance = Difference in time x (S1 x S2)/(S1 β S2) D = [12 β 8]/60 x {(40 x 48)/[48 β 40]} => (4/60) x (48 x 40)/8 => 16 km Time, T = D/S (take any one of the speed) => 16/40 = 16/40 x 60 = 24 minutes Then, correct time is 24 β 12 = 12 minutes
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