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Conversions between percents, decimals and fractions
Operations with percents
Percentage of a number
Percent change
Conversions between percents, decimals, and fractions
Given the frequency that percents occur, it is very important that you understand
what a percent is and are able to use percents in performing calculations. This unit
will help you learn the skills you need in order to work with percents.
Percent means "per one hundred" Symbol for percent is %
For example, suppose there are 100 students enrolled in a lecture class. If only 63
attend the lecture, then 63 per 100 students showed up. This means 63% of the
students attended the lecture.
If we take a closer look at this, we can see that the fraction of the students that
attended the lecture is 63/100, and this fraction can be expressed as 0.63.
• _63% is the same as 63/100
• _63% is the same as 0.63
This example shows how decimals, fractions, and percents are closely related and
can be used to represent the same information.
Converting between Percents and Decimals
Convert from percent to decimal:
To change a percent to a decimal we divide by 100. This is the same as moving the
decimal point two places to the left. For example, 15% is equivalent to the decimal
0.15.
Notice that dividing by 100 moves the decimal point two places to the left.