Multiple choice

A boat moves downstream at a rate of 9 kmph and upstream at a rate of 6 kmph. Find the speed of the boat in still water.

  1. 15 km/hr

  2. 12.5 km/hr

  3. 8.5 km/hr

  4. 7.5 km/hr
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D Correct answer
Explanation

The speed of a boat in still water is the average of its downstream and upstream speeds. Speed = (Downstream + Upstream) / 2 = (9 + 6) / 2 = 15 / 2 = 7.5 km/hr.

AI explanation

Using the formula for speed in still water, which is half the sum of the downstream and upstream speeds, add 9 kmph and 6 kmph to get 15 kmph. Dividing this total by 2 yields 7.5 kmph. The result is 7.5 km/hr.

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