Q1)-Two men starting from the same place walk at the rate of 5 km/h and 5.5 km/h respectively. What time will they take to be 8.5 km apart, if they walk in the same direction ?
Q2)-A walks around a circular field at the rate of one round per hour while B runs around it at the rate of six rounds per hour. They start in the same direction from the same point at 7.30 am. They shall first cross each other at:
Q3)-A walks at 4 km/h and 4 hours after his start , B cycles after him at 10 km/h. How far from the start does B catch up with A ?
Q4)-A thief is noticed by a policeman from a distance of 200 m . The thief starts running and the policemen chases him.The thief and the policeman run at the rate of 10 km and 11 km per hour respectively. What is the distance between them after 6 minutes ?
Q5)-A thief steals a car at 2:30 pm and drives it at 60 km/h. The theft is discovered at 3 pm and the owner sets off in another car at 75 km/h. When will he overtake the thief ?
Q6)-Two guns were fired from the same place at an interval of 10 minutes and 30 seconds , but a person in the train approaching the place hears the second shot 10 minutes after the first. The speed of the train ( in km/h) , supposing that speed travels at 330 metres per second is
Q7)-Two cyclists start from the same place in opposite directions. One goes towards north at 18 km/h and the other goes towards south at 20 km/h. What time will they take to be 47.5 km apart ?
Q8)-The distance between two cities A and B is 330 km. A train starts from A at 8 am and travels towards B at 60 km/h Another train starts from B at 9 am and travels towards A at 75 km/h. At what time do they meet ?
Q9)-The jogging track in a sports complex is 726 metres in circumference. Deepak and his wife start from the same point and walk in opposite directions at 4.5 km/h and 3.75 km/h respectively. They will meet for the first time in
Q10)-A and B walk around a circular track . They start at 8 am from the same point in the opposite directions. A and B walk at a speed of 2 rounds per hour and 3 rounds per hour respectively. How many times shall they cross each other before 9:30 am ?
4 hrs 15 min
8 hrs 30 min
16 hrs
17 hrs
Ans.- D
To be 0.5 km apart , they take 1 hour
To be 8.5 km apart , they take ( 1/0.5 x 8.5) hrs = 17 hrs
To be 0.5 km apart , they take 1 hour
To be 8.5 km apart , they take ( 1/0.5 x 8.5) hrs = 17 hrs
Q2)-A walks around a circular field at the rate of one round per hour while B runs around it at the rate of six rounds per hour. They start in the same direction from the same point at 7.30 am. They shall first cross each other at:
7:42 am
7:48 am
8:10 am
8:30 am
Ans.- A
Since A and B move in the same direction along the circle , so they will first meet each other when there is difference of one round between the two.
relative speed of A and B = ( 6 - 1 ) = 5 rounds per hour.
Time take to complete one round at this speed = 1/5 hr = 12 min
Since A and B move in the same direction along the circle , so they will first meet each other when there is difference of one round between the two.
relative speed of A and B = ( 6 - 1 ) = 5 rounds per hour.
Time take to complete one round at this speed = 1/5 hr = 12 min
Q3)-A walks at 4 km/h and 4 hours after his start , B cycles after him at 10 km/h. How far from the start does B catch up with A ?
16.7 km
18.6 km
21.5 km
26.7 km
Ans.- D
Suppose after x km from the start B catches up with A. Then the difference in the time taken by A to cover x km and that taken by B to cover x km in 4 hours
x/4 - x/10 = 4 or x = 26.7 km
Suppose after x km from the start B catches up with A. Then the difference in the time taken by A to cover x km and that taken by B to cover x km in 4 hours
x/4 - x/10 = 4 or x = 26.7 km
Q4)-A thief is noticed by a policeman from a distance of 200 m . The thief starts running and the policemen chases him.The thief and the policeman run at the rate of 10 km and 11 km per hour respectively. What is the distance between them after 6 minutes ?
100 m
150 m
190 m
200 m
Ans.- A
RElative speed of the thief and policeman = (11 - 10 ) km/h = 1 km/h
Distance covered in 6 minutes = (1/60 x 6) km =1/10 km = 100 m
RElative speed of the thief and policeman = (11 - 10 ) km/h = 1 km/h
Distance covered in 6 minutes = (1/60 x 6) km =1/10 km = 100 m
Q5)-A thief steals a car at 2:30 pm and drives it at 60 km/h. The theft is discovered at 3 pm and the owner sets off in another car at 75 km/h. When will he overtake the thief ?
4.30 pm
4.45 pm
5 pm
5.15 pm
Ans.- C
Suppose the thief is overtaken x hrs after 2:30 pm
Then distance covered by the thief in x hrs= distance covered by the owner in ( x - 1/2) hrs
60x = 75(x - 1/2)
x=5/2 hrs
So thief is overtaken at 5 pm
Suppose the thief is overtaken x hrs after 2:30 pm
Then distance covered by the thief in x hrs= distance covered by the owner in ( x - 1/2) hrs
60x = 75(x - 1/2)
x=5/2 hrs
So thief is overtaken at 5 pm
Q6)-Two guns were fired from the same place at an interval of 10 minutes and 30 seconds , but a person in the train approaching the place hears the second shot 10 minutes after the first. The speed of the train ( in km/h) , supposing that speed travels at 330 metres per second is
19.8
58.6
59.4
111.80
Ans.- C
LEt the speed of the train be x m/s. Then, Distance travelled by the train in 10 min. = Distance travelled by sound in 30 sec
x X 10 X 60 = 330 X 30
x = 16.5
Speed of the train = 16.5 m/sec = ( 16.5 x 18/5) km/h = 59.4 km/h
LEt the speed of the train be x m/s. Then, Distance travelled by the train in 10 min. = Distance travelled by sound in 30 sec
x X 10 X 60 = 330 X 30
x = 16.5
Speed of the train = 16.5 m/sec = ( 16.5 x 18/5) km/h = 59.4 km/h
Q7)-Two cyclists start from the same place in opposite directions. One goes towards north at 18 km/h and the other goes towards south at 20 km/h. What time will they take to be 47.5 km apart ?
1 1/4 hrs
2 1/4 hrs
2 hrs 23 min
2 1/2 hrs
Ans.- A
To be (18 + 20 ) km apart , they take 1 hours
To be 47.5 km apart , they take ( 1/38 x 47.5) hrs= 1 1/4 hrs
To be (18 + 20 ) km apart , they take 1 hours
To be 47.5 km apart , they take ( 1/38 x 47.5) hrs= 1 1/4 hrs
Q8)-The distance between two cities A and B is 330 km. A train starts from A at 8 am and travels towards B at 60 km/h Another train starts from B at 9 am and travels towards A at 75 km/h. At what time do they meet ?
10 am
10:30 am
11 am
11:30 am
Ans.- C
Suppose they meet x hrs after 8 am. Then , 60x + 75(x-1) = 330
they meet at (8 + 3 ) , i.e. 11 am
Suppose they meet x hrs after 8 am. Then , 60x + 75(x-1) = 330
they meet at (8 + 3 ) , i.e. 11 am
Q9)-The jogging track in a sports complex is 726 metres in circumference. Deepak and his wife start from the same point and walk in opposite directions at 4.5 km/h and 3.75 km/h respectively. They will meet for the first time in
4.9 min
5.28 min
5.5 min
6 min
Ans.- B
Clearly , the two will meet when they are 726 m apart
To be (4.5 + 3.75 ) = 8.25 km apart , they take 1 hour
To be 726 m apart , they take ( 100/825 x 726/1000) hrs = 5.28 min
Clearly , the two will meet when they are 726 m apart
To be (4.5 + 3.75 ) = 8.25 km apart , they take 1 hour
To be 726 m apart , they take ( 100/825 x 726/1000) hrs = 5.28 min
Q10)-A and B walk around a circular track . They start at 8 am from the same point in the opposite directions. A and B walk at a speed of 2 rounds per hour and 3 rounds per hour respectively. How many times shall they cross each other before 9:30 am ?
5
6
7
8
Ans.- C
Relative speed = ( 2 +3 ) = 5 rounds per hour
So they cross each other 5 times in an hour and 2 times in half an hour.
Hence they cross each other 7 times before 9:30 am
Relative speed = ( 2 +3 ) = 5 rounds per hour
So they cross each other 5 times in an hour and 2 times in half an hour.
Hence they cross each other 7 times before 9:30 am
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