# Time and Distance

Time and Distance - Important Points

1. | In what time an athlete can cover a distance of 500 m if he runs at a speed of 36 kmph? |
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A. 50 seconds

B. 55 seconds

C. 72 seconds

D. 80 seconds

View Answer Discuss Work SpaceAnswer: option a

Explanation:

Speed given = 36 kmph = 36 x 5 /18 m/sec = 10 m/sec

Distance to be covered = 500 m

Time taken = Distance / speed = 500 / 10 = 50 secs

2. | A train travels from City A to City B at a speed of 44 kmph, while on its return journey, it was travelling at speed of 77 kmph. The average speed (in Kmph) of the train is: |
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A. 56

B. 58.5

C. 60

D. 60.5

View Answer Discuss Work SpaceAnswer: option a

Explanation:

Let x be the speed of the train while going from City A to B.

Let y be the speed of the train while going from City B to A.

Average speed of the train is given by = 2xy / (x+y)

Average speed = (2 x 44 x 77) / (44 + 77 )

Average speed = 56

3. | A bus travels from City X to City Y at a speed of 32 kmph, while on its return journey, it travels at the speed of 96 kmph. Find the average speed of the bus (in kmph). |
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A. 64

B. 58

C. 48

D. 44

View Answer Discuss Work SpaceAnswer: option c

Explanation:

Let x be the speed of the bus while going from City X to Y. Let y be the speed going from City Y to X.

Average speed of the bus is given by = 2xy / (x+y)

Average speed = (2 x 32 x 96) / (32 + 96 )

Average speed = 48

4. | A car completes journey in 10 hrs, the first half at 21 kmph and the second half at 24 kmph. The distance covered (kms) is: |
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A. 224

B. 214

C. 234

D. 204

View Answer Discuss Work SpaceAnswer: option a

Explanation:

Let the distance to be covered be x km

Then x/2 km is travelled at a speed of 21 kmph and x/2 at 24 kmph

Time taken to covered whole journey is 10 hrs

=> x / (2 x 21) + x / (2 x 24) = 10

=> x / 42 + x / 48 = 10

=> 48x + 42x = 42*48*10

=> x = (42*48*10) / 90

=> x = 224

Distance covered = 224 km

5. | A person travels from city A to city B. During his onward journey his speed was 12 kmph and while returning his tripled his speed. His average speed (in kmph) is: |
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A. 18

B. 22

C. 24

D. 36

View Answer Discuss Work SpaceAnswer: option a

Explanation:

Speed of backward journey = 36 kmph

Average Speed = 2*12*36 / (12 + 36)

= 18 kmph