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प्रश्न
The table shows the time four elevators take to travel various distances. Find which elevator is fastest and which is slowest.
| Distance (m) | Time (sec.) | |
| Elevator- A | 435 | 29 |
| Elevator- B | 448 | 28 |
| Elevator- C | 130 | 10 |
| Elevator- D | 85 | 5 |
How much distance will be travelled by elevators B and C separately in 140 sec? Who travelled more and by how much?
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उत्तर
On the basis of given table,
Elevator A takes 29s to cover 435 m.
∴ Distance covered by elevator A in 1s = `435/29` = 15 m
Elevator B takes 28s to cover 448 m.
∴ Distance covered by elevator B in 1s = `448/28` = 16 m
Elevator C takes 10s to cover 130 m.
∴ Distance covered by elevator C in 1s = `130/10` = 13 m
Elevator D takes 5s to cover 85 m.
∴ Distance covered by elevator D in 1s = `85/5` = 17 m
Hence, in 1s, elevator D covers more distance as compare to elevators A, B and C. So, elevator D is fastest, while elevator C covers least. Hence elevator C is slowest.
Now, elevator B covers distance in 140s = 140 × 16 = 2240 m ...[∵ Distance = Speed × Time]
Elevator C covers distance in 140s = 140 × 13 = 1820 m
∴ Elevator B covers more distance than C = 2240 – 1820 = 420 m
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