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A woman jogs for 2 km at 8 km/h and then walks for 2 km

at 6 km/h. What is her average speed for the entire trip?

1 Answer

3 votes

Answer:

6 6/7 km/h

Explanation:

The relations between speed, time, and distance are ...

time = distance/speed

speed = distance/time

__

So, to find the average speed, we need to know the total distance and the total time. The distances are given, but we need to compute the times.

time jogging = (2 km)/(8 km/h) = 1/4 h

time walking = (2 km)/(6 km/h) = 1/3 h

Then the woman's average speed is ...

average speed = (total distance)/(total time) = (2 km + 2 km)/(1/4 h + 1/3 h)

= (4 km)/(7/12 h) = 48/7 km/h

= 6 6/7 km/h

User Jzilg
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