A crew row a boat 24 km upstream and 36 km downstream, taking 4 hours for each separate direction. Find the speed of the current stream. MCQ with Answer and Explanation

A crew row a boat 24 km upstream and 36 km downstream, taking 4 hours for each separate direction. Find the speed of the current stream.
A. 1.5 km/h
B. 2 km/h
C. 1.75 km/h
D. 1.25 km/h
Answer: Option A
Solution (By JKSSB Mock Tests)
Upstream speed = 24 / 4 = 6 km/h. Downstream speed = 36 / 4 = 9 km/h. Current speed = (Downstream speed - Upstream speed) / 2 = (9 - 6) / 2 = 1.5 km/h.

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Time Speed and Distance Questions

Question #1
A train passes a milestone in 6 seconds. If the speed of the train is 60 km/h, find the length of the train.
A. 80 meters
B. 100 meters
C. 150 meters
D. 120 meters

Correct Answer: Option B


Explanation:
Speed of train = 60 * (5/18) = 50/3 m/s. Length of train = Speed * Time = (50/3) * 6 = 100 meters.

This question belongs to: Maths Time Speed and Distance
Question #2
A sonar signal takes 6 seconds to travel down to an underwater reef and reflect back to the vessel. If the speed of sound in water is 1500 m/s, find the depth of the reef in kilometers.
A. 5.0 km
B. 4.2 km
C. 4.8 km
D. 4.5 km

Correct Answer: Option D


Explanation:
Total travel time to reef and back = 6 seconds. Time to reach reef = 3 seconds. Depth = Speed * Time = 1500 * 3 = 4500 meters = 4.5 km.

This question belongs to: Maths Time Speed and Distance
Question #3
A man covers 1/3rd of his journey at 20 km/h and the remaining 2/3rd at 40 km/h. If the total distance is 120 km, find the total time taken for the journey.
A. 4 hours
B. 5 hours
C. 3.5 hours
D. 4.5 hours

Correct Answer: Option A


Explanation:
First part distance = 120 / 3 = 40 km. Time1 = 40 / 20 = 2 hours. Remaining distance = 80 km. Time2 = 80 / 40 = 2 hours. Total time = 2 + 2 = 4 hours.

This question belongs to: Maths Time Speed and Distance