Boats and Streams Aptitude Practice Test - Set 01

Practice Test: Question Set - 01

---

1. A boat travel 8 km in 1 hr downstream and 4 km in 1 hr upstream. Find how much time this boat will take to travel 18 km in still water?

(A) 3 hrs

(B) 4 hrs

(C) 2 hrs 45 min

(D) 3 hrs 45 min

Answer: Option A

---

2. A man rows 1 km downstream in 20 minutes and upstream in 40 min. find the speed of man in still water:

(A) 2.25 kmph

(B) 2.5 kmph

(C) 3 kmph

(D) 3.5 kmph

Answer: Option A

---

3. A boat against the current of water goes 9 km/hr and in the direction of current 12 km/hr. The boat takes 4 hrs and 12 min to move upward and downward direction from P to Q. What is the distance between P and Q?

(A) 21.6 km

(B) 18 km

(C) 21 km

(D) 28 km

Answer: Option A
Solution:
(d/9) + (d/12) = 4 × (12/60)
Therefore, d = 21.6 km.

---

4. A man can row a certain distance downstream in 4 hrs and returns the same distance in 6 hrs. If the stream flows at the rate of 1 km/hr, then what will be the man’s speed if he rows in still water?

(A) 3 kmph

(B) 5 kmph

(C) 7 kmph

(D) 9 kmph

Answer: Option B
(x + y) × t₁ = (x – y) × t₂
or, (x + 1) × 4 = (x - 1) × 6
or, x = 5 kmph

---

5. A man rows, up the stream 15 km and down the stream 35 km taking 5 hrs each time. The velocity of the current is:

(A) 2 kmph

(B) 4.5 kmph

(C) 10 kmph

(D) 25 kmph

Answer: Option A
Solution:
(x - y) = 15/5 = 3........... (eq. 1)
And, (x + y) = 35/5 = 7............... (eq. 2)
From equation 1 and 2, we get; y = 2 kmph.

---

6. A boat can travel with a speed of 13 km/hr in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream.

(A) 2 hours

(B) 3 hours

(C) 4 hours

(D) 5 hours

Answer: Option C
Solution:
Speed downstream = (13 + 4) km/hr = 17 km/hr.
Time taken to travel 68 km downstream = (68/17) hrs = 4 hrs.

---

7. A man's speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr. The man's speed against the current is:

(A) 8.5 km/hr

(B) 9 km/hr

(C) 10 km/hr

(D) 12.5 km/hr

Answer: Option C
Solution:
Man's rate in still water = (15 - 2.5) km/hr = 12.5 km/hr.
Man's rate against the current = (12.5 - 2.5) km/hr = 10 km/hr.

---

8. In one hour, a boat goes 11 km/hr along the stream and 5 km/hr against the stream. The speed of the boat in still water (in km/hr) is:

(A) 3 km/hr

(B) 5 km/hr

(C) 8 km/hr

(D) 9 km/hr

Answer: Option C
Solution:
Speed in still water = ½ (11 + 5) kmph = 8 kmph.

---

9. A boat running downstream covers a distance of 16 km in 2 hours while for covering the same distance upstream, it takes 4 hours. What is the speed of the boat in still water?

(A) 4 km/hr

(B) 6 km/hr

(C) 8 km/hr

(D) Data inadequate

Answer: Option B
Solution:
Rate downstream = (16/2) kmph = 8 kmph.
Rate upstream = (16/4) kmph = 4 kmph.
∴ Speed in still water = ½ (8 + 4) kmph = 6 kmph.

---

10. The speed of a boat in still water in 15 km/hr and the rate of current is 3 km/hr. The distance traveled downstream in 12 minutes is:

(A) 1.2 km

(B) 1.8 km

(C) 2.4 km

(D) 3.6 km

Answer: Option D
Solution:
Speed downstream = (15 + 3) kmph = 18 kmph.
Distance travelled = [18 × (12/60) ] km = 3.6 km.

---

11. A boat covers a certain distance downstream in 1 hour, while it comes back in 1½hours. If the speed of the stream be 3 kmph, what is the speed of the boat in still water?

(A) 12 kmph

(B) 13 kmph

(C) 14 kmph

(D) 15 kmph

Answer: Option D
Solution:
Let the speed of the boat in still water be x kmph. Then,
Speed downstream = (x + 3) kmph,
Speed upstream = (x - 3) kmph.
∴ {(x + 3) × 1} = {(x - 3) × (3/2)}
=> 2x + 6 = 3x - 9
=> x = 15 kmph.

---

12. A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 10 minutes. How long will it take to go 5 km in stationary water?

(A) 40 minutes

(B) 1 hour

(C) 1 hr 15 min

(D) 1 hr 30 min

Answer: Option C
Solution:
Rate downstream = {(1/10) × 60} km/hr = 6 km/hr.
Rate upstream = 2 km/hr.
Speed in still water = ½(6 + 2) km/hr = 4 km/hr.
∴ Required time = (4/5) hrs = 1¼ hrs = 1 hr 15 min.

---

13. Speed of a boat in standing water is 9 kmph and the speed of the stream is 1.5 kmph. A man rows to a place at a distance of 105 km and comes back to the starting point. The total time taken by him is:

(A) 16 hours

(B) 18 hours

(C) 20 hours

(D) 24 hours

Answer: Option D
Solution:
Speed upstream = (9 - 1.5) kmph = 7.5 kmph.
Speed downstream = (9 + 1.5) kmph = 10.5 kmph.
Total time taken = {105/7.5) + (105/10.5)} hours = 24 hours.

---

14. A boat moves down the stream at the rate of 1 km in 6 min and up the stream at the rate of 1 km in 10 min. The speed of current is:

(A) 2 kmph

(B) 2.5 kmph

(C) 3 kmph

(D) 3.5 kmph

Answer: Option A
Solution: Speed in downstream = x + y = 1km / 6 min = 10 kmph............... (eq. 1)
Speed in upstream = x - y = 1 km / 10 min = 6 kmph............. (eq. 2)
Subtracting equation (2) from equation (1), we get
y= 2 kmph

---

15. A man can row upstream a distance of 1/2 km in 10 min and return the same distance downstream in 5 min. Find the ratio of man’s speed in still water and that of the stream.

(A) 8 : 3

(B) 3 : 1

(C) 3 : 8

(D) 1 : 3

Answer: Option B
Solution:
(x + y) × t₁ = (x – y) × t₂
Or, (x + y) × 5 = (x - y) × 10
Therefore, x/y = 3/1

---

View All Answers

1. Answer: Option A 2. Answer: Option A 3. Answer: Option A 4. Answer: Option B 5. Answer: Option A 6. Answer: Option C 7. Answer: Option C 8. Answer: Option C 9. Answer: Option B 10. Answer: Option D 11. Answer: Option D 12. Answer: Option C 13. Answer: Option D 14. Answer: Option A 15. Answer: Option B

---

 Boats and Streams: Next Tests:

Formulas

Solved Example: 01

Practice Test: 01