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Question
The odometer of a car reads 57321.0 km when the clock shows the time 08:30 AM. What is the distance moved by the car, if at 08:50 AM, the odometer reading has changed to 57336.0 km? Calculate the speed of the car in km/min during this time. Express the speed in km/h also.
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Solution
Initial reading of the odometer of the car = 57321.0 km
The final reading of the odometer of the car = 57336.0 km
Distance covered by the car
= Final reading of the odometer of the car - Initial reading of the odometer of the car
= 57336.0 - 57321.0
= 15 km
The given car starts at 8:30 a.m. and stops at 8:50 a.m.
Therefore, the time taken by the car to cover the distance is (8:50 − 8:30) min = 20 min
Distance covered by the car = 15 km
Time taken by the car = 20 min
Speed = `"Distance covered"/"Time taken" `
= `15/20`
= 0.75 km/min
Again
60 min = 1 h
20 min = `1/60 xx 20`
= `1/3` h
Time taken by the car = `1/3` h
Speed = `"Distance covered"/"Time Taken"`
= `15/(1/3)`
= 45 km/h.
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