# Can anyone please help explain how to do 3 b? Thanks!

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The motorist reads his/her speedometer as the car starts from rest and finds that, at 5 minute intervals, the speed is 0, 5, 10, 15, 19, 22, 26, 30, 33, 35, 38 and 40 km/h. It is assumed that the speed over the entire 5 minute duration is the same as that at the end of the interval.

The distance traveled by the motorist in each 5 minute interval is the product of the speed at the end of the interval and `(5*60)*(1000/3600)` . The total distance traveled in the first hour is: (5*60)*(1000/3600)*(0 + 5 + 10+ 15 + 19 + 22 + 26+ 30+ 33+ 35+ 38 + 40) = 22750 m or 22.75 km.

**The distance traveled by the motorist in the first hour is 22.75 km**