Solve this multiple-choice question and choose the correct option.

A boat cover a distance of 30 km downstream in 2 h while it takes 6 h to cover the same distance distance upstream. What is the speed of the boat (in km/h)?

5
7.5
13
10

Correct Answer: 10

Explanation:

Speed of boat downstream = Distance covered / Time taken = 30/2 = 15 km/h Now, speed of boat upstream = Distance covered / Time taken = 30/6 = 5 km/h Now, speed of boat = (Speed download + Speed upstream) / 2 = (15 + 5) / 2 = 10 km/h

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