In order to solve problems that deal with percentage of increase or decrease, you should be able to:
When a beginning and ending amount are given and you are asked to find the
percent of increase or decrease from the beginning amount to the ending amount, you need to use the formula shown below:
In other words, find out how much the increase or decrease was. Then divide that by the original amount given in the problem. Once you have this number as a
fraction or a decimal, change it to a
percent to find your answer.
Suppose the average attendance at a local high school's football games went down from 2000 people in 2003 to 1500 people in 2004. What was the
percent decrease in attendance at the football games?
The
solution to this problem begins by finding how much the decrease was.
This is done by taking 2000 - 1500 = 500.
So the amount of decrease is 500.
Now we divide that number by the original amount, or the football attendance in 2003, which was 2000.
So the
conclusion is that football attendance decreased by 25% from 2003 to 2004.