Definitions:

From Wolfram MathWorld:

The use of percentages is a way of expressing ratios in terms of whole numbers. A ratio or fraction is converted to a percentage by multiplying by 100 and appending a "percentage sign" %.

Percent -- from Wolfram MathWorld

A percent can always be written as a decimal, and a decimal can be written as a percent, by moving the decimal point two places to the right like this $$0.15 = 15 \% $$

A general example to help you recognize patterns and spot the information you're looking for

15% Tip $${ $47.60 * 15 = 714}$$ Divide the answer by 100 $${714 / 100 = $7.14 }$$

We use percentages when calculating tips for everyday services.

Describing the Meaning of Percent

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Length: 3:01

Converting Decimals to Percents

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Length: 2:36