Final answer:
Percentages are primarily used to express a fraction of a whole, describe a change in quantity, and compare proportions. Calculating percentages involves dividing the part by the total and multiplying by 100 while visual representations like pie graphs showcase the relative sizes expressed as percentages.
Step-by-step explanation:
Percentages serve various fundamental purposes. They can be used to express a fraction of a whole, describe a change in quantity or compare proportions relative to a whole. Here are examples for each use:
- Expressing a Fraction: "Of the total sales last month, 15% were from electronics."
- Describing a Change: "After the recent update, the app's speed has improved by 25%."
- Comparing Proportions: "In the survey, 60% preferred coffee while 40% favored tea over coffee."
To calculate percentages, divide the part by the total and multiply by 100. In terms of conversion, a percent can be turned into a fraction by placing the percentage number over 100 or into a decimal by dividing the percentage number by 100
Regarding visual representation, in a pie graph, each slice represents a share of the total which is shown as a percentage. For example, a slice showing 25% indicates a quarter of the pie, representing a quarter of the total.
The three basic uses of percentages are:
Expressing a fraction of something. For example, a company started with 15,000 employees and has grown 3% within the past year.
Describing a change in something. For example, out of 3,000 employees, 15% received a raise.
Comparing two quantities. For example, the shoes are 50% lighter but are 17% more expensive.