7th Grade Math

366 Percent

Chapter Study

Guide and Review

Be sure the following

Key Concepts are noted

in your Foldable.

Key Concepts

Percents (Lesson 1)

• To find the percent of a number, first write the
  percent as either a fraction or decimal and then
  multiply.

Proportions and Equations (Lesson 2)

• Percent Proportion
  part
  
  whole
  = 100 n percent


• Percent Equation
  part = percent · whole
  Applying Percents (Lesson 3)


• A percent of change is a ratio that compares the
  change in quantity to the original amount.

percent of change =

amount of change

__

original amount

• Discount is the amount by which the regular price
  of an item is reduced. The sale price is the regular
  price minus the discount.


• Sales tax is an additional amount of money
  charged on items. The total cost of an item is the
  regular price plus the sales tax.

Key Vocabulary

discount

gratuity

percent equation

percent of change

percent of decrease

percent of increase

percent proportion

principal

sales tax

simple interest

tip

Vocabulary Check

State whether each sentence is true or false.

If false, replace the underlined word or

number to make a true sentence.

1. The sale price of a discounted item is the
   regular price minus the discount.


2. A ratio that compares the change in
   quantity to the original amount is called
   the percent of change.


3. A percent proportion compares part of a
   quantity to the whole quantity using a
   percent.


4. The formula for simple interest is I = prt.


5. One way to find the total bill with tip is to
   add the percent of tip to 10%.


6. The equation part = percent · whole is
   known as the principal equation.


7. The principal is the amount of money
   deposited or borrowed.


8. A tax is the amount by which the regular
   price of an item is reduced.


9. To find a percent of increase, compare the
   amount of the increase to the new amount.


10. If the new amount is greater than the
    original amount, then the percent of
    change is percent of decrease.

1B 1C

2B 2C

3B 3C

3D3D 3E

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