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.