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प्रश्न
Meenakshee cycles to her school at an average speed of 12 km/h and takes 20 minutes to reach her school. If she wants to reach her school in 12 minutes, her average speed should be ______.
विकल्प
`20/3` km/h
16 km/h
20 km/h
15 km/h
उत्तर
Meenakshee cycles to her school at an average speed of 12 km/h and takes 20 minutes to reach her school. If she wants to reach her school in 12 minutes, her average speed should be 20 km/h.
Explanation:
Given, speed of cycle = 12 km/h
Time taken by Meenakshee through cycle = 20 min
Then, total distance cover = `(12 xx 20)/60` = 4 km ...[∵ Distance = Time × Speed]
If Meeanakshee want to reach her school in 12 min, then her cycle speed should be `4/(12/60)` i.e. 20 km/h. ...`[because "Speed" = "Distance"/"Time"]`
Hence, 20 km/h
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