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Question
A racing car covered 600 km in 3 hours 20 minutes. Find its speed in metre per second. How much distance will the car cover in 50 sec?
Solution
Distance covered = 600 km
Time taken = 3 hr 20 min
= `3 20/60=3 1/3=10/3`hrs
∴ Speed in km/h = `"Distance"/"Time"`
= `600/(10/3)`
= `(600xx3)/10` km/h
= 180 km/h
and Speed in m/sec = `(180xx1000)/(60xx60)`
= 50 m/sec
and Distance covered in 50 seconds
= Speed × Time
= 50 × 50 m
= 2500 m or 2.5 km
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