Every morning, Jack has a routine of jogging a certain distance at 20 Km/h helped by wind at his back. On his return jog, being weary and pushing against the wind, he jogs the same distance at 12 Km/h. What is Jack's AVERAGE jogging speed? Thanks for help.
Since the distance is not given in this question, will assign the distance an arbitrary number of 10 Km. It makes no difference what the distance is when calculating the average speed:
10/20 = 1/2 hour-the time it takes him on his outgoing jog.
10/12 =5/6 hours-the time it takes him on his return jog.
[2 x 10] / [1/2 + 5/6] = 20 / (4/3) =20 x 3/4 =15 Km/h - Jack's average jog back and forth.
