Question

The odometer of a car reads 57321km when the clock shows the time 8:30a.m what is distance moved by a car if at 8:50 a.m the odometer reading has changed to 57336km . Calculate the speed of the car km per minute and per hour also.

Answer 1

the distance travelled will be 57336-57321
=15 km
therefore speed = 15/20=0.75km/hr
therefore speed= 15×60/20=45 km/hr

Answer 2

Distance traveled at 8:30 a.m -- 57321 km
Final distance traveled at 8:50 a.m -- 57336 km
Distance traveled between 8:30 and 8:50 am -- 57336-57321=15 km
Time taken -- 20 mins( since 8:30 to 8:50 is 20 minutes)

So,speed of car in km per minute = 15/20 km per min.= 0.75 km per min.
in km per hour=  15/20 X 60 = 45 kmph.

So the speed of car is 45kmph or 0.75 km per min if it covers 15km in 20 minutes.