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CBSE Class 9 Answered

Please refer the image attached for the question. Please answer as soon as possible.
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Asked by Rajendra | 19 Jan, 2019, 09:36: AM
answered-by-expert Expert Answer
For shortest time boat must travel perpendicular to the flow of river.
So time taken =t equals space fraction numerator s over denominator u space end fraction equals space fraction numerator 4 to the power of blank over denominator square root of left parenthesis 4 squared minus 2 squared end root end fraction equals space fraction numerator 4 over denominator square root of 12 end fraction space equals 1.15  hour
So option c is closest value to this value.
Answered by Ankit K | 19 Jan, 2019, 10:35: PM

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CBSE 9 - Physics
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