Multiple choice

A boat covers 24 km upstream and 36 km downstream in 6 hours, while it covers 36 km upstream and 24 km downstream in 13/2 hour. The velocity of the current is

  1. 2.4 km/hr

  2. 2 km/hr

  3. 3 km/hr

  4. 0.75 km/hr

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let u be upstream speed and v be downstream speed. 24/u + 36/v = 6 and 36/u + 24/v = 6.5. Solving this system gives u = 8 and v = 12. Current speed = (v - u)/2 = (12 - 8)/2 = 2 km/hr.

Keep practicing — related questions