Multiple choice

The speed of a boat in still water is $8$ km/hr and speed of the stream is $3$ km/hr. Find time taken by the boat to go $55$ km downstream.

  1. $5$ hrs
  2. $3$ hrs
  3. $2$ hrs
  4. $4$ hrs
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A Correct answer
Explanation

Downstream speed = 8 + 3 = 11 km/hr. Time = Distance / Speed = 55 / 11 = 5 hours.

AI explanation

Using the downstream speed formula, add the speed of the boat in still water to the speed of the stream, giving 8 km/hr plus 3 km/hr, which equals 11 km/hr. Then, using the formula time equals distance divided by speed, divide the downstream distance by this speed: 55 km divided by 11 km/hr equals 5 hrs.

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