Pierre drives to work a distance of 51 miles at a speed of 7
Pierre drives to work (a distance of 51 miles) at a speed of 71 mph and returns home at a speed of 56 mph. What is his average speed for the round trip? Use the harmonic mean.
Pierre drives to work (a distance of 51 miles) at a speed of 71 mph and returns home at a speed of 56 mph. What is his average speed for the round trip? Use the harmonic mean.
Pierre drives to work (a distance of 51 miles) at a speed of 71 mph and returns home at a speed of 56 mph. What is his average speed for the round trip? Use the harmonic mean.
Solution
To get the average speed, we get the harmonic mean of the two velocities.
Thus,
vave = 2 / (1/71 + 1/56) = 62.61417323 mph or 62 78/127 mph [ANSWER]
