Question
The speed of current is 30 km/hr. If the speed of the
boat in still water had been 13 km/hr more than the original speed then it would take 7.5 hours to cover 420 km in downstream. Find the original speed of the boat in still water (in km/h).Solution
Let the speed of the boat in still water be ‘x’ km/hr According to the question, (x + 13 + 30) = 420/7.5 Or, x = 56 – 43 = 13
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