7th Grade Math

190 Rational Numbers

Chapter Study

Guide and Review

Key Vocabulary

bar notation

common denominator

least common denominator

(LCD)

like fractions

monomial

negative exponent

rational numbers

repeating decimal

scientific notation

standard form

terminating decimal

unlike fractions

Vocabulary Check

Choose the correct term or number to

complete each sentence.

1. 1.875 is an example of a (terminating,
   repeating) decimal.


2. A common denominator for the fractions
   32 and ^14 is (7, 12).


3. To add like fractions, add the (numerators,
   denominators).


4. When dividing by a fraction, multiply by
   its (value, reciprocal).


5. Fractions with different denominators are
   called (like, unlike) fractions.


6. The mixed number 2 ^47 can be renamed
   as ( 2 ^77 , 1 _^117 ).


7. When multiplying fractions, multiply the
   numerators and (multiply, keep) the
   denominators.


8. Fractions, terminating decimals, and
   repeating decimals are (integers, rational
   numbers).


9. 3.16 × 103 is expressed in (scientific
   notation, standard form).


10. The least common denominator for ^58
    and 127 is (4, 24).

Key Concepts

Terminating and Repeating Decimals

(Lesson 1)

• A terminating decimal is a decimal whose digits
  end. Repeating decimals have a pattern in their
  digits that repeats forever.

Adding and Subtracting Fractions (Lesson 2)

• To add or subtract fractions, rename the fractions
  using the LCD. Then add or subtract the
  numerators and write the result over the
  denominator.

Multiplying and Dividing Fractions (Lesson 3)

• To multiply fractions, multiply the numerators and
  multiply the denominators.


• To divide by a fraction, multiply by its
  multiplicative inverse, or reciprocal.

Scientific Notation (Lesson 4)

• A number is expressed in scientific notation when
  it is written as the product of a factor and a power
  of 10. The factor must be greater than or equal to
  1 and less than 10.

Be sure the following

Key Concepts are noted

in your Foldable.

2-3 Multiply and Divide Fractions

2-2 Add and Subtract Fractions

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