2. Comparing Fractions By: Greg Stark EC&I 831

3. Why compare fractions? To determine which fraction represents a larger value Fractions with the same denominator are called like fractions and can be compared by their numerators The larger fraction has the biggest numerator 7878 5858 >

4. What if the they are unlike fractions? 4747 3535 It can be difficult to determine which fraction is larger by looking at a diagram

5. What if they are unlike fractions? To determine which fraction represents a larger value with unlike fractions: 1.Multiply each denominator by the opposite numerator Important: always cross multiply from denominator (bottom) to opposing numerator (top) or this method will not work 4747 3535 < 2.Write the product (answer) beside the numerator 3.The side with the largest product, is the larger fraction 7 X 3 = 21 5 X 4 = 20

6. What if there are more than two fractions? This method will still work You must compare each fraction to the others to ensure you have them in the correct order – a time consuming process Converting all of the fractions to like terms is another method which may make this easier This method is discussed in the Adding Unlike Fractions presentation

7. Review: to compare fractions 1.For like fractions, the larger fraction is the one with the larger numerator 2.For unlike fractions, multiply opposing denominators (bottom) to numerators (top) – The side with the largest product is the larger fraction