Page 129 - ICSE Math 6

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5. A 80 m long train crosses a 60 m platform in 9 seconds. Find the speed of the train in km h .
6. Rohan and Tarun start running from the same place at the same time. If Rohan’s speed is
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4 km h and Tarun’s speed is 6 km h , find the distance between them after 4 hours if they run in:
(a) the same direction (b) opposite directions
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7. Find the length of a platform (in m) which a woman crosses at a speed of 6 km h in
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2 minutes.
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8. A bus covers the first 128 km in 2 hours, next 240 km in 3 hours and the remaining 280 km in
4 hours. Find the average speed of the bus.
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9. Saira drives her car with a uniform speed of 45 km h . Find:
(a) the distance covered by her in 2 hour 20 minutes
(b) time taken by her to cover 285 km

(c) her speed in m min –1
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10. Which is greater: a speed of 130 km h or a speed of 38 m s ?
11. A swimmer swims 300 m in still water and then returns following the same path. He takes a total
of 12 minutes to come back to his initial position. Find his speed in:

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(a) m s (b) km h –1

THINK SMART

1. Deepti is travelling to Delhi by a bus. On her way, two milestones appear at an interval of
8 minutes indicating that Delhi is 680 km and 670 km away respectively. If both milestones are
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on a straight road, at what speed, in km h , is the bus moving?
2. The table shows the time taken by the five students to complete a sack race.

Students Parth Hari Ali John Maya
Time taken (in s) 60 52 48 58 56

(i) Whom among them is the winner?
(ii) If the track was 60 m long, find the winner’s speed.

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