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2. • km/hr to m/s conversion:
1 kmph = 5 m/s
18
• m/s to km/hr conversion:
1 m/s = 18 m/s
5

3. Example:
Two cars start from A and B travel towards each other at
speeds of 50 km/h and 60 km/h respectively. At the time of
their meeting, the second car has travelled 12 kms more
than the first. Find the distance between A and B ?
Solution:
Starting at the same time but from different points, the
time taken by the cars to reach the meeting point are equal.
Hence, it can be inferred that the time is constant for both
the cars to reach the meeting point.
The ratio of the speeds of car A to car B is S1:S2 =50:60= 5:6
The ratio of the distance travelled by them is D1:D2 = 5:6

4. Example:
If the car had gone from A to B at 50 kmph and
returned from B to A at 60 kmph, what would be
the average speed?
Solution:
Let d be the A – B distance,
Then the average speed = d + d/ t1 + t2
= 2d / {(d/s1) + (d/s2)}
= 2* s1*s2 / (s1 + s2)
= 2 * 50 * 60 / (50 + 60)
= 54 6/11 kmph.

5. Example:
A boy goes to school at a speed of 3 km/hr and
returns to village at 2 km/hr. If he takes 5 hours,
what is the distance between the school and the
village?
Solution:
Distance between school and village is
= 5 * (3*2) / (3+2)
= 6 km

6. Example:
A man covers a certain distance between his
house and office on bike. Having an average
speed of 30 km/hr, he is late by 10 minutes.
However, with a speed of 40 km/hr, he reaches
his office 5 minutes earlier. Find the distance
between his house and office?
Solution 1:
Difference in time;
10+5 = 15 minutes = 15/60 hours = 0.25 hours
The required distance = (30×40)x0.25/(40-30)
= 30 km

7. Example:
Two, trains, one from Howrah to Patna and the
other from Patna to Howrah, start
simultaneously. After they meet, the trains
reach their destinations after 9 hours and 16
hours respectively. The ratio of their speeds is:
Solution:
The ratio of their speed is √16/√9 = 4/3 or 4:3

8. Question
A person crosses a 600 m long street in 5
minutes. What is his speed in km per hour?
A. 3.6 km/hr
B. 7.2 km/hr
C. 8.4 km/hr
D. 10 km/hr

9. • Ans: B
• Speed = (6005×60) m/sec= 2 m/sec = 2 x
(18/5) km/hr = 7.2 km/hr

10. Question
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?
A. 9 min
B. 10 min
C. 12 min
D. 20 min

11. Practice Questions
1. A man covers a certain distance by car driving at
30kmph and he returns back to the starting point
with a speed 40kmph. Find his average speed for
the whole journey.
a) 35 km/hr
b) 34.3 km/hr
c) 36 km/hr
d) None
Ans: B

12. 2. The ratio between the speeds of two trains is
7 : 8. If the second train runs 400 km in 4 hours,
What is the speed of the first train?
a) 85km/hr
b) 87.5 km/hr
c) 90 km/hr
d) None
Ans: B

13. 3. A truck covers a distance of 550 meters in 1
minute whereas a train covers a distance of 33
kms in 45 minutes. What is the ratio of their
speed?
a) 4:3
b) 3:4
c) 5:4
d) None
Ans: B

14. 4. A person has to cover a distance of 6 km in 45
minutes. If he covers one-half of the distance in two-
thirds of the total time; to cover the remaining distance
in the remaining time, what should be his speed in
km/hr?
a) 10 km/hr
b) 12 km/hr
c) 15 km/hr
d) None
Ans: B

15. 5. A man travels the first part of his journey at 30
kmph and the remaining part at 90 kmph, and he
covers the entire journey at an average speed of 50
kmph. What is the ratio of the distance he covered at
30 kmph to that he covered at 90 kmph?
a) 1 : 2
b) 1 : 3
c) 2 : 3
d) 3 : 4
Ans: C

16. 6. Paras starts from Ludhiana at 6 a.m. at a
constant speed of 40 kmph. He halts at
Jalandhar for half an hour and then drives at 70
kmph. He reaches Amritsar at 9.30 a.m. which is
180 km away from Ludhiana. What is the
distance between Jalandhar and Amritsar?
a) 120 km
b) 140 km
c) 100 km
d) 130 km
Ans: B

17. 7. There are 20 windmills with a constant distance
between each pole. A car takes 22 seconds to reach
the 12th pole. How much time will it take to reach
the last pole?
a) 36 seconds
b) 38 seconds
c) 40 seconds
d) 42 seconds
Ans: B

18. 8. By walking at 3/7th of his usual speed, a man
reaches office 20 minutes later than usual time.
What is his usual travel time?
a) 10 min
b) 15 min
c) 20 min
d) 25 min
Ans: B

19. 9. Two buses travel to a place at 45 km/h and 60
km/h respectively. If the second bus takes 5 1/2
hours less than the first for the journey, the length
(all in km) of the journey is
a) 900
b) 945
c) 990
d) 1350
Ans: C

20. 10. If I walk at 30 miles/hr I reach 1 hour before
the reporting time and if I walk at 20 miles/hr I
reach 1 hour late. Find the distance between 2
points and the exact time of reaching
destination is 11 am then find the speed with
which I have to walk to reach on time.
a) 100miles and 24 miles/hr
b) 120miles and 24 miles/hr
c) 120miles and 16 miles/hr
d) 100miles and 16 miles/hr
Ans: B

21. 11. A ship went on a voyage. After 180 miles a
plane started with 10 times speed that of the ship.
Find the distance when they meet from starting
point.
a) 185 miles
b) 190 miles
c) 200 miles
d) 220 miles
Ans: C

22. 12. While driving from Chennai to Bangalore, I
covered half of the journey at an average speed of
80 kmph, half of the 2nd half of the journey at an
average speed of 40 kmph and the rest at
60kmph. It took 5 hours and 30 minutes to reach
Bangalore. How far is Bangalore from Chennai?
a) 310 km
b) 350 km
c) 330 km
d) 360 km
Ans: C

23. 14. Anil and Jagjeet want to go from Coimbatore to
Ooty. There are two ways to do this. First way is to
hire a two wheeler, second is to go by bus. Jagjeet
started immediately to Ooty in a non stop bus. After
sometime Anil hired a Yamaha bike and started
towards Ooty. Anil overtook Jagjeet at 10.00 a.m.
Anil reached Ooty at 12.30 p.m. and spent an hour.
While returning from Ooty, he met the bus at 2.00
p.m. When will the bus reach Ooty?
a) 2.30 p.m.
b) 3.00 p.m.
c) 3.30 p.m.
d) 4.00 p.m.
Ans: B

24. 1. A train running at the speed of 60 km/hr
crosses a pole in 9 seconds. What is the length
of the train?
A. 120 metres
B. 180 metres
C. 324 metres
D. 150 metres
Ans: D

25. 2. The length of the bridge, which a train 130
metres long and travelling at 45 km/hr can cross
in 30 seconds, is:
A. 200 m
B. 225 m
C. 245 m
D. 250 m
Ans: C

26. 3. A train passes a station platform in 36
seconds and a man standing on the platform in
20 seconds. If the speed of the train is 54 km/hr,
then what is the length of the platform?
a) 200 m
b) 240 m
c) 300 m
d) 864 m
Ans: B

27. 4. A train 125 m long passes a man, running at 5
km/hr in the same direction in which the train is
going, in 10 seconds. The speed of the train is:
A. 45 km/hr
B. 50 km/hr
C. 54 km/hr
D. 55 km/hr
Ans: B

28. 5. Two trains are moving in opposite directions @
60 km/hr and 90 km/hr. Their lengths are 1.10 km
and 0.9 km respectively. The time taken by the
slower train to cross the faster train in seconds is:
A. 36
B. 45
C. 48
D. 49
Ans: C

29. 6. A jogger running at 9 kmph alongside a railway
track in 240 metres ahead of the engine of a 120
metres long train running at 45 kmph in the same
direction. In how much time will the train pass the
jogger?
A. 3.6 sec
B. 18 sec
C. 36 sec
D. 72 sec
Ans: C

30. 7. A 270 metres long train running at the speed
of 120 kmph crosses another train running in
opposite direction at the speed of 80 kmph in 9
seconds. What is the length of the other train?
A. 230 m
B. 240 m
C. 260 m
D. 320 m
Ans: A