Arithmetic

Time, Speed & Distance

Medium

applied

A man rows downstream 30 km and upstream 20 km. If he takes 5 hours to cover each distance, then the speed of stream is

5 km/hr

1 km/hr

4 km/hr

6 km/hr

✅ Correct Option: 2

A man is rowing a boat downstream 30 km in 5 hours and upstream 20 km in 5 hours.

When rowing downstream, the effective speed is the man's speed plus the stream's speed.

When rowing upstream, the effective speed is the man's speed minus the stream's speed.

Let man's speed in still water = $m$ km/hr

Let stream's speed = $s$ km/hr

Using Speed = Distance ÷ Time

Downstream speed = $30 \div 5$

Downstream speed = $6$ km/hr

$m + s = 6$ ... (1)

Upstream speed = $20 \div 5$

Upstream speed = $4$ km/hr

$m - s = 4$ ... (2)

Subtracting equation (2) from equation (1):

$(m + s) - (m - s) = 6 - 4$

$m + s - m + s = 2$

$2s = 2$

$s = 1$

Therefore, the speed of the stream is $1$ km/hr.

2025: 27 May Shift 1

A swimmer whose speed in swimming pool is 5 km/h, swims between two points in a river and returns back to starting point. He took 20 minutes more to cover the distance upstream than to cover downstream. If the speed of stream is 2 km/h, then the distance between two points is

2025: 22 May Shift 1

A man rows 24 km upstream in 6 hours and 36 km downstream in 6 hours each time, then the speed of the boat in the still water is

2026: 22 May Shift 1

A boat can travel 36 km upstream in 5 hours. If the speed of the stream is 2.4 km/hr, how much time will the boat take to cover a distance of 78 km downstream?

2025: 13 May Shift 1

A swimmer whose speed in still water is 6 km/hr, swims between two points in a river and returns to the starting point. He took 20 minutes more to cover the distance upstream than downstream. If the speed of the stream is 3 km/hr, then the distance between the two points is:

2026: 19 May Shift 1

A man rows a boat downstream 30 km and upstream 20 km. It takes him 5 hours to cover each distance. Which of the following are TRUE?

(A) The speed of the boat in still water is 10 km/hr.

(B) The speed of the boat in still water is 5 km/hr.

(D) The speed of the current is 6 km/hr.

Choose the correct answer from the options given below:

2025: 19 May Shift 1

In a 700 m race, the ratio of speeds of two participants A and B is 5:6. If A has a start of 150 m, then the distance by which A wins the race is:

A man rows downstream 30 km and upstream 20 km. If he takes 5 hours to cover each distance, then the speed of stream is

Solution

Related questions:

Keyboard Shortcuts

CUET Mathematics Past Year Questions (Topic-Wise)