### Home > PC3 > Chapter 10 > Lesson 10.1.2 > Problem10-40

10-40.

A car’s distance from home is given in the following table. Assume the car started from home.

 Time (min) $5$ $7$ $10$ $15$ $20$ $35$ $45$ Distance (miles) $1.25$ $2$ $1$ $0$ $1.5$ $5$ $18$
1. Calculate the average velocity in miles per hour for each interval.

First interval, 5 - 7 minutes:

$\text{average velocity }=\frac{2-1.25}{7-5}$

2. What does a positive velocity indicate? A negative velocity?

The first interval has a positive velocity and the distance changes from $1.25$ miles from home to $2$ miles from home.
The second interval has a negative velocity and the distance from home changes from $2$ miles to $1$ mile.

3. What was the average velocity for the entire 45 minutes? Was the car ever traveling at that rate?

$\text{average velocity }=\frac{18-1.25}{45-5}$

4. Write a scenario to describe the car’s trip. Be sure to include the times that any changes were taking place.