Fractions, Decimals and Percents Products and Factors Multiplying Fractions Common Denominator Signs of a Fraction Lowest Common Multiple Finding the LCM Adding and Subtracting Fractions Improper Fractions

Fractions, Decimals and Percents (cont.) Mixed Numbers Multiplying and Dividing

Mixed Numbers Adding and Subtracting

Mixed Numbers Changing from Decimal to Percent Changing from Percent to Decimal

Products and Factors

Key Point: When two (or more) whole numbers are

multiplied, the result is called the product of those numbers.

The two (or more) original numbers are called the factors of the product.

Multiplying Fractions

Rule 4‑l:

To multiply fractions cancel factors that are in both numerators and

denominators, multiply the remaining numerators (their product

is the numerator of the answer), multiply the remaining denominators (their

product is the denominator of the answer).

Common Denominator

Key Point: When the denominators of fractions are

identical, that number is the common denominator (CD).

Signs of a Fraction

Rule 4‑2: Any two signs of a fraction may be

changed without changing the value of the fraction.

Lowest Common Multiple

Key Point: The lowest common multiple (LCM) of

two or more numbers is the lowest multiple that is common to each of them.

Finding the LCM

Rule 4‑3:

To find the LCM of two or more numbers: Factor each term; determine the maximum number of times a

prime factor appears in any one term; multiply the resulting prime factors found in

step 2. This number is the LCM.

Adding and Subtracting Fractions

Rule 4‑4: To add or subtract fractions with unlike denominators: Find the CD Change the denominator of all fractions to

this denominator Add the fractions combining all like terms in

the numerator. Reduce to lowest terms.

Improper Fractions

Key Point. When the numerator is greater than the

denominator, the fraction is called an improper fraction.

Mixed Numbers

Key Point: Numbers that have a whole number part

and a fractional part are called mixed numbers.

Multiplying and Dividing Mixed Numbers

Key Point: To multiply or divide mixed numbers,

change the mixed numbers to improper fractions and perform the function as before.

Adding and Subtracting Mixed Numbers

Key Point: To add and subtract, change all mixed

numbers to improper fractions Perform the function as with proper

fractions

Changing from Decimal to Percent

Rule 4‑5: To change a decimal number to a

percent, multiply by 100 and add the % sign.

Changing from Percent to Decimal

Rule 4‑6: To change from a percent to a decimal

number, divide the number by 100 and remove the % sign.