Lesson 41

​Finding a percent of a number

​To describe part of a group we often use a fraction of a percent.

• Three-fourths of the students voted for Rowan​

• Tim answered 80% of the questions correctly

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​Often used to describe financial situations.

• 30% of the regular price

• the Sales tax rate is 7%

• The bank pays 3% interest​

​How to find a percent of a number

​a percent can be changed to decimal and back

25% = 25/100

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5% = 5/100

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75% = ​75/100

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​write as a decimal and fraction(reduced)

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​40 % =

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70% =

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10% =

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25% =​

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​What number is 75% of 20.

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​How to solve:

​Can change percent to a fraction:

75% = 75/100 = 3/4​

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solve

3/4 of 20​

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​Can change percent to decimal:

75% = .75​

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solve

​.75 of 20

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​Tim answered 80% of the 25 questions. How many questions did he get correct?

​The sales tax rate was 6%. Find the tax on a $12.00 purchase

​10% of 350

​How much money is 8% of $15.00?

​Erik sold 80% of her 30 baseball cards. How many baseball cards did he sell?