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Math: Basic Tutorials : Introduction to Percentage
Introduction to Percentage
Percentages are essentially fractions where the denominator is 100. To show that a number is a percent, we use the percent symbol (%) beside the number. For example, if you got 75 questions right out of 100 on a test (75/100), you would have scored 75%. This section gives an introduction to percentages and how to work with them.
Examples
Convert 55 percent to a fraction.
Line 1: Percent represents a fraction with a denominator of 100, so rewrite the percent as 55 over 100.
Line 2: Reduce the fraction to lowest terms by dividing both the numerator and denominator by 5.
Line 3: Simplify to get the fraction 11 over 20.
Convert 55 percent to a decimal.
Line 1: Percent represents a fraction with a denominator of 100, so rewrite the percent as 55 over 100.
Line 2: Divide the numerator by the denominator. Note that since we are dividing by 100, this is the same as moving the decimal in the numerator 2 spots to the left.
Line 3: Simplify so the decimal is 0 decimal 5 5 or 55 hundredths.
Convert 0 decimal 2 5 to a percent.
Line 1: Multiply the decimal by 100 percent so is 0 decimal 2 5 times 100 percent. Note that this is the same as moving the decimal 2 spots to the right.
Line 2: Simplify and keep the percent as part of your answer so the answer is 25 percent.
to a percent.
Convert 42 over 60 to a percent.
Line 1: Convert a fraction to a decimal by dividing the numerator by the denominator, so it is 42 dividing by 60.
Line 2: Simplify to 0 decimal 7.
Line 3: Multiply the decimal by 100 percent so it is 0 decimal 7 times 100 percent.
Line 4: Simplify and keep the percent as part of your answer so the answer is 70 percent.
Source: "Prealgebra - opens in a new window" by Lynn Marecek & Mary Anne Anthony-Smith is licensed under CC BY 4.0 - opens in a new window / A derivative from the original work - opens in a new window
Summary and Worksheet
- Summary: Introduction to Percent - PDF - Opens in a new windowThis document contains a short (1 – 2 page) summary of this topic as well as detailed examples to illustrate key concepts. Use this summary to review this topic.
- Worksheet: Introduction to Percent - PDF - Opens in a new windowThis document contains practice questions on this topic. Use the worksheet to test your knowledge and practice the skills learned in this module. The answers to the practice questions are provided at the end.