Subtracting fractions 2
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The document provides instructions for subtracting fractions with unlike denominators using the least common denominator (LCD). It explains that the LCD is the smallest multiple that two denominators have in common. It then demonstrates finding the LCD and renaming the fractions with a common denominator before subtracting the numerators and simplifying the resulting fraction if possible. Examples are provided for clarifying each step of the process.
Subtracting fractions 2
- 1. Subtracting Fractions Kory Wilson Grand Canyon University Team Red TEC 539 Dr. Holly Strickland
- 2. Least Common Denominator (LCD same as LCM): The smallest multiple that two denominators have that are the same. LCD is used to find equivalent fractions when subtracting fractions with unlike denominators. Example: 1 2 multiples of 2 are: 2, 4, 6 , 8, 10. . . (2 x 3 =6) LCD = 6 1 3 multiples of 3 are: 3, 6 , 9, 12, 15 . . . (3 x 2 = 6) Terms to Know
- 3. Equivalent Fractions: Equivalent fractions are two fractions with the same value. Just as in money, one can represent the value of fifty cents with two quarters or five dimes. Although there is more than one way to represent of fifty cents, it’s worth is still the same. There may be multiple ways to represent one value in fractions too. The rule with equivalent fractions is, “What you do to the numerator, you must do to the denominator to keep it equal”. Example: 1 x 2 2 2 x 2 4 Terms to Know OR
- 4. Greatest Common Factor (GCF): The largest factor that can be evenly divided into two other numbers. Commonly used to reduce fractions into simplest form. Example: Find the GCF of the following fraction. 4 Factors of 4 are: 1, 2, 4 12 Factors of 12 are: 1, 2, 3, 4 ,6,12 GCF of 4 and 12 is 4 . Simplify fraction by dividing numerator and denominator by the GCF 4 . 4 4 1 12 4 3 Terms to Know
- 5. Step 1: When the denominators are the same, only subtract the numerators. Denominator in the answer is the same as in the equation. Do not subtract denominators. 5 3 2 8 8 8 Step 2: Simplify to simplest form using GCF . 2 factors of 2 are: 1, 2 8 factors of 8 are: 1, 2 , 4, 8 GCF is 2 2 2 1 8 2 4 How to Subtract Simple Fractions Answer in simplest form .
- 6. Step 1: Rename both fractions to an equivalent fraction with the same denominators by using the LCD. (See LCD definition) 2 2 6 8 ( 2 x 4) 8 ( 2 x 3) 6 ( 6 x 4) 24 ( 8 x 3) 24 Step 2: Subtract numerators and simplify using GCF. 8 6 2 2 1 24 24 24 2 12 How to Subtract Fractions with Unlike Denominators Multiples 6: 6, 12, 18, 24 . . . 8: 8, 16, 24 , 32 . . . LCD: 24 Factors: 2: 1, 2 24: 1, 2 , 3, 4, 6, 8, 12, 24 GCF: 2
- 7. Eather, J. (2010). A Maths dictionary for kids . Retrieved: July 4, 2010 from http://amathsdictionaryforkids.com/dictionary.html Math is fun . (2010). Retrieved: July 4, 2010 from http://www.mathsisfun.com/ References