Question
A boat covers a certain distance upstream in 6 hrs and
comes back to starting point with current in 3 hrs, If boat's upstream speed is 15 km/hr, then, find the distance travelled by boat in downstream in 7 hours?Solution
Time taken by boat upstream (u) = 6 hrs Time taken by boat downstream (v) = 3 hrs Speed of boat in upstream = 15 km/h Distance travelled by boat in upstream = 15 × 6 = 90 km we know that, u + v = 90/3 = 30 u – v = 15 Distance travelled by boat downstream = 7 × 30 = 210 km
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