Finding a Percent of a Number

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Presentation transcript:

Finding a Percent of a Number

Using a Proportion Set up a proportion that uses the percent over 100. Cross multiply to write an equation. Solve the equation. To set up your proportion, think, “IS over OF equals PERCENT over 100.”

Example – What is 20% of 30? x 20 = 30 100 100x = 30(20) 100x = 600 part = 30 100 whole 100x = 30(20) 100x = 600 100 100 x 6 =

Using a Decimal Change the percent to a decimal. Multiply that decimal by the number you are finding the percent of.

Example – What is 18% of 70? 18% = 0.18 0.18 x 70 = 12.6