Exercise 3 Page 181

Let's start by recalling that a percent of change is a ratio that compares the change in quantity to the original amount. If the original quantity is increased, then it is called a percent of increase. If the original quantity is decreased, then it is called a percent of decrease. To determine the percent of change, we can use the following formula. Percent of change =Amount of change/Original amount We know that Tyler bought the comic book for $ 49.62 last year, and he sold it for $ 52.10 this year. We can find the amount of change by subtracting the less value from the greater one. Amount of change = $ 52.10 - $ 49.62 = $ 2.48 Now let's use the formula to find the percent of change. To make the math easier, we can ignore the units for now.

Percent of change=Amount of change/Original amount

SubstituteII

Amount of change= 2.48, Original amount= 49.62

Percent of change=2.48/49.62

UseCalc

Use a calculator

Percent of change=0.049979...

RoundDec

Round to 2 decimal place(s)

Percent of change≈ 0.05

To write the decimal as a percent, we need to move the decimal point two places to the right and write the percent symbol.

Percent of change ≈ 0.05

WritePercent

Convert to percent

Percent of change ≈ 5 %

We found that the percent of change of the price of the comic book is about 5 %.