Glencoe Math: Course 2, Volume 1
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Glencoe Math: Course 2, Volume 1 View details
5. Percent of Change
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Exercise 21 Page 149

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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 According to the given table, 13.3 million children played soccer in 2008 and 13.8 million children played soccer in 2012. We can find the amount of change by subtracting the lesser value from the greater one. Amount of change = ( 13.8 - 13.3) million= 0.5million The amount of change is 0.5 million. Now we can use the formula to find the percent of change.

Percent of change=Amount of change/Original amount
Percent of change=0.5million/13.3million
Percent of change=0.037593...
Percent of change ≈ 0.038

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 ≈ 0.038
Percent of change ≈ 3.8 %

We got that the percent of change is about 3.8 %. Since the original quantity is increased, this is a percent of increase. Therefore, from 2008 to 2012, the number of children who played soccer increased by about 3.8 %.

Recall 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 According to the given table, 13.7 million children played soccer in 2006 and 13.3 million children played soccer in 2008. We can find the amount of change by subtracting the lesser value from the greater one. Amount of change = ( 13.7 - 13.3) million= 0.4million The amount of change is 0.4 million. Now we can use the formula to find the percent of change.

Percent of change=Amount of change/Original amount
Percent of change=0.4million/13.7million
Percent of change=0.029197...
Percent of change ≈ 0.029

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 ≈ 0.029
Percent of change ≈ 2.9 %

We got that the percent of change is about 2.9 %. Since the original quantity is decreased, this is a percent of decrease. Therefore, from 2006 to 2008, the number of children who played soccer decreased by about 2.9 %.