Fractions,%20Decimals%20and%20Percents

1
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

2
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

3
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.

4
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).

5
Common Denominator

• Key Point
• When the denominators of fractions are identical,
  that number is the common denominator (CD).

6
Signs of a Fraction

• Rule 4-2
• Any two signs of a fraction may be changed
  without changing the value of the fraction.

7
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.

8
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.

9
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.

10
Improper Fractions

• Key Point.
• When the numerator is greater than the
  denominator, the fraction is called an improper
  fraction.

11
Mixed Numbers

• Key Point
• Numbers that have a whole number part and a
  fractional part are called mixed numbers.

12
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.

13
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

14
Changing from Decimal to Percent

• Rule 4-5
• To change a decimal number to a percent, multiply
  by 100 and add the sign.

15
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.