# Maya drives from New York City to Boston at a rate of 40 MPH and drives at a rate of 60 MPH on the return trip. What was his average speed for the entire trip? Use the Harmonic mean to compute? Construct the HM geometrically?

##### 1 Answer

Aug 26, 2016

The Average Speed is

#### Explanation:

Suppose that the distance between New York City and Boston is

Time reqd. for this trip, at the rate of

The return journey is at the rate of

trip.

Thus, total distance of

Hence, the Average Speed for the complete journey is given by,

Distance/Time, i.e.,

Those who are familiar with Harmonic Mean will, at a glance, say

that the Average Speed for the trip is **not** the **Arithmetic Mean**

but the **Harmonic Mean** of the speeds.

Numerically, the Average Speed is

Enjoy Maths.!