Calculating Percent of Change

The percent change is the change in percent when a quantity has changed. It is calculated by writing a ratio of the amount of change to the original amount as a percent. Percent Change=Amount of Change/Original Amount For example, buying a collector's item for $12 and selling it for $15 results in a profit. What is the percent change? It can be calculated in four steps.

Determine if the Change is an Increase or a Decrease

Determine if the price of the item increases or decreases by looking at the difference between the new and original amounts.

Increase	New amount > Original amount
Decrease	Original amount > New amount

The change represents an increase since 15 is greater than 12.

Calculate the Amount of Change

When the change is an increase, subtract the original amount from the new amount to find the difference. Since the new amount is greater than the original amount, the difference will be positive. 15 - 12 = 3

Calculate the Ratio for Percent of Change

Now that the amount of increase and the original amounts are known, find the ratio of these amounts.

3/12

ReduceFrac

a/b=.a /3./.b /3.

1/4

CalcQuot

Calculate quotient

0.25

Write the Result as a Percent

As a final step, write the obtained number as a percent by multiplying 0.25 by 100. 0.25 * 100 =25 The percent of change is 25 %. This means that the price of the collector's item increased by 25 %.

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