In this video, we will be learning how to determine percent change. After you finish this lesson, view all of our Pre-Algebra lessons and practice problems.

Percent Change Formula:

For example:

The price of gas was originally $5. The new price for gas is $4. What is the percent change?

Substitute the givens

Simplify

## Examples of Percent Change

### Example 1

The staff at a company went from 40 to 29 employees. What is the percent decrease in staff?

First, substitute the given

Then, simplify

### Example 2

Jessica works in a candystore for $8.00 per hour. If her pay is increased to $14.00, then what is her percent increase in pay?

First, substitute the given

Then, simplify

## Video-Lesson Transcript

In this video, we will be learning how to determine percent change.

Let’s go through percent increase and percent decrease.

We will use just one formula to compute the percent change:

For example:

The price of gas was originally . The price went down to . What is the percent change?

Let’s use the formula.

Which will be

Then divide by the answer is

We have a decrease.

Let’s have another one.

The price of gas was originally . The price went down to . What is the percent change?

Let’s use the formula and substitute all the given values.

We’ll get

Since the answer is positive, it means it’s an increase.

Just a review, the percent change formula is