**Goal:** Hone the concept of average velocity

**Source:** CTtil2;12;02

While traveling from Boston to Hartford, Person A drives at a constant

speed of 55 mph for the entire trip. Person B drives at 65 mph for half

the trip and then drives 45 mph for the second half of the trip. When

would B arrive in Hartford relative to A?

- B arrives before A.
- B arrives at the same time as A.
- B arrives after A.
- Not enough information.

## Commentary:

## Answer

(3) Many students are inclined to average the speeds and conclude that

they arrive at the same time. It is often useful to compare this

situation to the one in which time is halved.