# How do you calculate the percent change of 24 to 21?

Feb 27, 2017

See the entire solution process below:

#### Explanation:

The formula for change in percent is:

$p = \frac{N - O}{O} \cdot 100$

Where:
$p$ is the percentage change.
$N$ is the New Value - 21 for this problem
$O$ is the Old Value - 24 for this problem

Substituting and calculating gives:

$p = \frac{21 - 24}{24} \cdot 100$

$p = - \frac{3}{24} \cdot 100$

$p = - \frac{300}{24}$

$p = 12.5$

The change was 12.5%