A man drives for two hours at a speed of 78 km/h, stops to get a coffee for fifteen minutes, and then continues for another hour and a half at a speed of 85 km/h.
What is his average speed?
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A man drives for two hours at a speed of 78 km/h, stops to get a coffee for fifteen minutes, and then continues for another hour and a half at a speed of 85 km/h.
What is his average speed?
In the first stage, we want to find the distance the truck traveled in its total journey,
We will use the data we already have,
78 km/h for two hours of driving and 85 km/h for an additional hour and a half.
78*2+85*1.5=
156+127.5=
283.5 km
Now, we want to discover the total duration of the journey.
We know there were two hours of driving, a quarter-hour break, and another hour and a half of driving,
Meaning:
2+0.25+1.5=
3.75 hours
Now, we'll divide the travel distance by the number of hours
285/3.75=
75.6 km/h
And that's the average speed!
km/h
A man drives for two hours at a speed of 78 km/h, stops to get a coffee for fifteen minutes, and then continues for another hour and a half at a speed of 85 km/h.
What is his average speed?
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