Time and Distance problems
- 1. A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is:
Options- A. 35.55 km/hr
- B. 36 km/hr
- C. 71.11 km/hr
- D. 71 km/hr Discuss
Correct Answer: 71.11 km/hr
Explanation:
| Total time taken = | ❨ | 160 | + | 160 | ❩hrs. | = | 9 | hrs. |
| 64 | 80 | 2 |
| ∴ Average speed = | ❨ | 320 x | 2 | ❩km/hr | = 71.11 km/hr. |
| 9 |
- 2. Excluding stoppages, the speed of a bus is 54 kmph and including stoppages, it is 45 kmph. For how many minutes does the bus stop per hour?
Options- A. 9
- B. 10
- C. 12
- D. 20 Discuss
Correct Answer: 10
Explanation:
| Time taken to cover 9 km = | ❨ | 9 | x 60 | ❩min | = 10 min. |
| 54 |
- 3. In covering a distance of 30 km, Abhay takes 2 hours more than Sameer. If Abhay doubles his speed, then he would take 1 hour less than Sameer. Abhay's speed is:
Options- A. 5 kmph
- B. 6 kmph
- C. 6.25 kmph
- D. 7.5 kmph Discuss
Correct Answer: 5 kmph
Explanation:
| Then, | 30 | - | 30 | = 3 |
| x | 2x |
⟹ 6x = 30
⟹ x = 5 km/hr.
- 4. It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the cars is:
Options- A. 2 : 3
- B. 3 : 2
- C. 3 : 4
- D. 4 : 3 Discuss
Correct Answer: 3 : 4
Explanation:
| Then, | 120 | + | 480 | = 8 ⟹ | 1 | + | 4 | = | 1 | ....(i) |
| x | y | x | y | 15 |
| And, | 200 | + | 400 | = | 25 | ⟹ | 1 | + | 2 | = | 1 | ....(ii) |
| x | y | 3 | x | y | 24 |
Solving (i) and (ii), we get: x = 60 and y = 80.
∴ Ratio of speeds = 60 : 80 = 3 : 4.
- 5. A man covered a certain distance at some speed. Had he moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. The distance (in km) is:
Options- A. 35
- B.
36 2 3 - C.
37 1 2 - D. 40 Discuss
Correct Answer: 40
Explanation:
| Then, | x | - | x | = | 40 | ⟹ 2y(y + 3) = 9x ....(i) |
| y | y + 3 | 60 |
| And, | x | - | x | = | 40 | ⟹ y(y - 2) = 3x ....(ii) |
| y -2 | y | 60 |
On dividing (i) by (ii), we get: x = 40.
- 6. Robert is travelling on his cycle and has calculated to reach point A at 2 P.M. if he travels at 10 kmph, he will reach there at 12 noon if he travels at 15 kmph. At what speed must he travel to reach A at 1 P.M.?
Options- A. 8 kmph
- B. 11 kmph
- C. 12 kmph
- D. 14 kmph Discuss
Correct Answer: 12 kmph
Explanation:
| Then, | x | - | x | = 2 |
| 10 | 15 |
⟹ 3x - 2x = 60
⟹ x = 60 km.
| Time taken to travel 60 km at 10 km/hr = | ❨ | 60 | ❩hrs | = 6 hrs. |
| 10 |
So, Robert started 6 hours before 2 P.M. i.e., at 8 A.M.
| ∴ Required speed = | ❨ | 60 | ❩kmph. | = 12 kmph. |
| 5 |
- 7. A and B are 20 km apart. A can walk at an average speed of 4 km/hr and B at 6 km/h. If they start walking towards each other at 7:000 am, when they will meet?
Options- A. 8:00 am
- B. 8:30 am
- C. 9:00 am
- D. 10:00 am Discuss
Correct Answer: 9:00 am
Explanation:
Suppose they will meet after T hours.
Distance = Speed x Time
Sum of distance traveled by them after T hours
6T + 4T = 20 km
T = 2 hours.
So they will meet at 7:00 AM + 2 hours = 9:00 AM
- 8. Arjun runs a distance of 1500 m in 5 minutes. What is his speed in Km/hr?
Options- A. 16 km/hr
- B. 18 km/hr
- C. 15 km/hr
- D. 20 km/hr Discuss
Correct Answer: 18 km/hr
Explanation:
Speed = (1500/300 ) m/sec
= 5 m/sec
= (5 x 18/5 ) km/hr
= 18 km/hr
- 9. In how many minutes will Rohit cover a distance of 800 m, if he runs at speed of 10 km/hr?
Options- A. 5 min 12 sec
- B. 4 min 40 sec
- C. 5 min
- D. 4 min 48 sec Discuss
Correct Answer: 4 min 48 sec
Explanation:
Rohit's speed = 10 Km/hr = (10 x 5/18) m/sec = 50/18 m/sec
Time taken to cover 800 m = (800 / (50/18) ) sec
= (800 x 18/50) sec = 288 sec = 4 min 48 sec
- 10. A plane flies along the four sides of a square field at a speed of 200, 400, 600 and 800 km/hr. Then find the average speed of plane around the square field.
Options- A. 394
- B. 400
- C. 414
- D. 384 Discuss
Correct Answer: 384
Explanation:
Let the side of the square field be x and the average speed of plane be y
x/200 + x/400 + x/600 + x/800 = 4x/y
? 25x/2400 = 4x/y
? y =384
? Average speed is 384 km/hr
More in Aptitude:
Programming
Copyright ©CuriousTab. All rights reserved.