Question

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

Answer 1

Answer:

  6 6/7 km/h

Step-by-step 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