In this module, you can study how to calculate percent increase and percent decrease.
The video above shows a quick method for calculating percent increase or decrease. At the end, she quickly converts the decimal number answer to a percent by moving the decimal point two places to the right. If you're unclear how to do this, see "Converting decimals to percents" under the "Decimals" tab.
100 reduced by 25% is 75, but 75 increased by 25% is not 100!
If an house price increases 20% one year and 10% the next year, it has gone up 32% (not 30%!) of the original value.