Multiple choice

A boat can travel 30 km in one hour in still water and travels the same distance against the stream in 90 minutes. How much time will the boat take to travel 80 km in the direction of the stream?

  1. 5 hours

  2. 3 hours

  3. 2 hours

  4. 2.5 hours
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Boat speed in still water is 30 km/h. Upstream speed is 20 km/h (30 km in 90 minutes), so stream speed is 10 km/h. Downstream speed is 40 km/h, taking 80/40 = 2 hours for 80 km.

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