Multiple choice

Directions: Study the given information carefully to answer the question that follows: The speeds of Boat A and Boat B are in the ratio 4 : 5. The speed of the current with respect to Boat A is 1/4th and with respect to Boat B is 1/5th. Find the distance covered downstream by Boat B in 1.5 hours and speed of current is 5 km/hr.

  1. 36 km

  2. 40 km

  3. 42 km

  4. 45 km

  5. 48 km
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let speed of A = 4k, B = 5k. Current speed = 5. Current relative to A = 1/4 * 4k = k = 5. So speed of A = 20, B = 25. Downstream speed of B = 25 + 5 = 30. Distance = 30 * 1.5 = 45 km.

AI explanation

The speed of the current is 5 km/hr, which is one-fifth of Boat B's speed, making Boat B's speed 25 km/hr. The downstream speed is calculated by adding the speed of the current to the boat's speed, giving 25 plus 5, which equals 30 km/hr. Using the distance formula, the distance covered downstream in 1.5 hours is 30 multiplied by 1.5, resulting in 45 km.

Keep practicing — related questions