Thursday 24 March 2011

Time, Distance and Speed Questions:



1. Walking at ¾ of his usual speed a person is late by 10 min, find his usual travel time.

2. Walking at 10km/hr, Gaurav reaches his college 2 hr early. If he walks at 15 km/hr, he is 2 hr 40min early. Find the distance between his college and the residence.

3. A man running at 12 kmph is pursued by a dog running at 16 kmph. If the distance between the man and the dog is 300 meters when the dog started running, how much time will it take for the dog to overtake the man?

4. A student walks from his house at a speed of 21/2 kms/ hr and reaches his school 6 minutes late. The next day he increases his speed by 1 km/hr and reaches his school 6 minutes early. How far is the school from his house?

5. A train running between two towns arrives at its destination 10 minutes late when it goes 40 kms per hour and 16 minutes late when it goes 30 kms per hr. Find the distance between the two towns.

6. Salim was going from Paris to Budapest via Rome, a distance of 1200 km, by train. From Paris he takes the TGV, which travels at 500 km/hr, and gets down at Rome. Then, he immediately takes a bike and rides the remaining part of the journey at a speed of 200 km/hr. If he takes a total of three hours from Paris to Budapest, what is the distance (in kms) from Paris to Rome?

7. A traveler walks a certain distance. Had he gone half a kilometer an hour faster, he would have walked it in 5 4 th of the time, and had he gone half a km an hour slower, he would have traveled 2 2 1 hours longer. What is the distance?

8. The average speed of a train including stoppages was 27 kms/hr and excluding stoppages was 41 kms/hr. How many minutes did the train stop per hour.

9. A bullock cart has to cover a distance of 80 km in 10 hours. If it covers half of the journey in (3/5) of the time, what should be its speed to cover the remaining distance in the time left?

10. A person has to make a journey of 72 kms. He rides a cycle at 12 kms/hr. After going a certain distance, the cycle is punctured and he walks the remaining distance at 4 ½ kms/hr. Find when the cycle is punctured if the total time for the jouney is 8 ½ hrs.

11. After traveling 30 min, a train met with an accident and was stopped there for 45 min. Due to the accident, its speed reduced to 2/3 to its former speed and the train reached its destination 1hr 30 min late .Had the accident occurred 60km after the point it occurred earlier, the train would have reached 30 min earlier. Find the length of the journey.

12. A dog at point A goes in pursuit of a fox 30m away. The dog takes a leap of 2 m against 1 m long leaps of the fox. If the dog makes two leaps to the fox’s three, at what distance from A will the dog catch up with the fox?

13. In a 500m race Runman beats Bhagtaram by 100m. In 800m race Bhagtaram beats Padtabhau by 200m. By how much did Runman beat Padtabhau in a race of 1000 m?

14. In a 500 metres race, the ratio of speeds of two contestants A and B is 3 : 4. A has a start of 140 metres. Then by what distance by A wins.

15. In a 100 metres race, A can beat B by 25 metres and B can beat C by 4 metres. In the same race, by what distance A can beat C.

16. A 60 metres long train travelling at 42 kms/hr crosses a train 84 metres long travelling at 30 kms/hr in the same direction. How long will it take to fully cross it?

17. Two trains of same length moving in opposite directions have their speeds in the ratio 2: 3. They take 10 seconds to cross each other. The faster train takes 25 seconds to cross a stationary train 500 meters long. What is the length of either train?

18. Train A when going from X to Y takes 20 sec to pass Train B. Train A takes the same time at the same speed to pass Train B when it is going from Y to X. Which of the following is true:
1) The speed to train B was reduced.
2) The speed of train B remains unchanged.
3) The speed of train B was increased.
4) This is not possible.

19. Which of the following is true :

(a) Two trains of different length with different but constant speeds can take less time to cross each other when moving in same direction and more time when traveling in opposite direction.

(b) Two trains of different length traveling at same constant speed will be able to cross each other after a certain time when moving in same direction.

(c) Two trains of same length are traveling at same constant speed. The ends of the two train will be maximum apart from each other when the trains are traveling in 90 degrees to each other.

(d) There are two trains A and B with speed C and D respectively. They take X and Y time to pass each other when moving in same direction and in opposite direction respectively. When the speeds of the two trains are interchanged the time taken in both directions to pass each will remain the same as earlier.

20. Two trains, 676 and 338 meters long take 39 seconds to cross each other while traveling in the same direction and take only 13 seconds when they cross in opposite directions. What are the speeds at which the trains are traveling?
21. There are two trains one of which is 275 meters long traveling at 48 meters/ sec. They take 25 seconds to cross each other while traveling in the same direction and take 5 seconds when they cross in opposite directions. What is the speed and length of the second train?

22. There are two trains, one of which is 588 meters long and traveling at 105 mt/sec and the other one is 392 meters long traveling at 35 meters/ sec. How long will it take to cross each other while traveling in the same direction and when they cross in opposite directions?

23. There are two trains whose combined length is 480 and the difference between their length is 240. They take 30 seconds to cross each other while traveling in the same direction and take only 20 seconds when they cross in opposite directions.What are the lengths of the two trains? What are the speeds at which the trains are traveling?

24. There are two trains one of which is 252 meters long traveling at 31 meters/ sec. They take 21 seconds to cross each other while traveling in the same direction and take 10 seconds when they cross in opposite directions. What is the speed and length of the second train?

25. There are two trains, one of which is 468 meters long and traveling at 41 mt/sec and the other one is 312 meters long traveling at 11 meters/ sec. How long will it take to cross each other while traveling in the same direction and when they cross in opposite directions?

26. There are two trains whose combined length is 1140 and the difference between their lengths is 228. They take 38 seconds to cross each other while traveling in the same direction and take 30 seconds when they cross in opposite directions. What are the lengths of the two trains? What are the speeds at which the trains are traveling?

27. There are two trains one of which is 828 meters long traveling at 38 meters/ sec. They take 46 seconds to cross each other while traveling in the same direction and take 30 seconds when they cross in opposite directions. What is the speed and length of the second train?

28. There are two trains, one of which is 420 meters long and is traveling at 40 mt/sec and the other one is 252 meters long traveling at 8 meters/ sec. How long will it take to cross each other while traveling in the same direction and when they cross in opposite directions?

29. Two trains, 456 and 209 meters long take 19 seconds to cross each other while traveling in the same direction and take only 5 seconds when they cross in opposite directions. What are the speeds at which the trains are traveling?

30. There are two trains one of which is 391 meters long traveling at 27 meters/ sec. They take 34 seconds to cross each other while traveling in the same direction and take 17 seconds when they cross in opposite directions. What is the speed and length of the second train?

31. There are two trains, one of which is 360 meters long and traveling at 27 mt/sec and the other one is 288 meters long traveling at 9 meters/ sec. How long will it take to cross each other while traveling in the same direction and when they cross in opposite directions?

32. There are two trains whose combined length is 608 mts and the difference between their lengths is 160 mts. They take 16 seconds to cross each other while traveling in the same direction and take only 8 seconds when they cross in opposite directions. What are the lengths of the two trains? What are the speeds at which the trains are traveling?

33. There are two trains one of which is 345 meters long traveling at 76 meters/ sec. They take 15 seconds to cross each other while traveling in the same direction and take 5 seconds when they cross in opposite directions. What is the speed and length of the second train?

34. There are two trains, one of which is 504 meters long and traveling at 34 mt/sec and the other one is 312 meters long traveling at 17 meters/ sec. How long will it take to cross
each other while traveling in the same direction and when
They cross in opposite directions?

35. 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.

36. A boat running upstream takes 8 hours 48 minutes to cover a certain distance, while it takes 4 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively?

37. A motorboat, whose speed in 15 km/hr in still water goes 30 km downstream and comes back in a total of 4 hours 30 minutes. Find the speed of the stream (in km/hr).

38. 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?

39. A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, Find the speed of the stream.

40. A man can row at 5 kmph in still water. If the velocity of current is 1 kmph and it takes him 1 hour to row to a place and come back, how far is the place?

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

42. 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?

43. 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. Find the total time taken by him.

44. A man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. The ratio of the speed of the boat (in still water) and the stream is?

45. Ajay can row three quarters of a kilometer against the current in 11 ¼ minutes and returns in 7 ½ minutes. Find the speed of man in still water.


2 comments:

  1. Q1. Ans is 30 minutes.
    Let the initial velocity be = V1
    Distance = D
    Time = T1
    And new velocity be = V2
    Time = T2 = T1+10
    since velocity V = D/T
    and D is same in both the cases, V is inversely proportional to T
    i.e. (V1/V2) = (T2/T1)
    V1 = (V2T2/T1)
    = [3V1*(T1+10)]/4T1
    On simplifying we'll get T1 = 30

    ReplyDelete
  2. Thanks Ranjani...Is there any Easier Method too?

    ReplyDelete