# The Walzer's average phone bill increased from $16.65 to$19.98 what is the percent of increase?

May 28, 2017

See a solution process below:

#### Explanation:

The formula for calculating the percent change in a value between two points in time is:

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

Where:

$p$ is the percent change - what we are solving for in this problem.

$N$ is the New Value - $19.98 in this problem. $O$is the Old Value -$16.65 in this problem.

Substituting and solving for $p$ gives:

p = ($19.98 -$16.65)/($16.65) *100 p = ($3.33)/($16.65) *100 p = ($333)/($16.65) $p = 20\$

The Walzer's phone bill increased 20%