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6 11 5 55 6 66 if ad bc then using the example above

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Unformatted text preview: on with the larger numerator is the larger fraction. Example: Which is larger, Solution: The least common denominator is 66. 8 48 = 11 66 5 Therefore, is the larger fraction. 6 a c Method II—To compare with , compare the cross products as follows: b d ac > bd ac If ad < bc, then < bd ac If ad = bc, then = bd 5 8 or ? 6 11 5 55 = 6 66 If ad > bc, then Using the example above, to compare 5 is the larger fraction. 6 5 8 with , compare 5 · 11 with 6 · 8. Since 5 · 11 is greater, 6 11 Sometimes, a combination of these methods must be used in comparing a series of fractions. When a common denominator can be found easily for a series of fractions, Method I is easier. When a common denominator would result in a very large number, Method II is easier. Example: Which of the following fractions is the largest? (A) (B) (C) (D) (E) Solution: To compare the last four, we can easily use a common denominator of 64. 11 44 55 7 56 = = 16 64 64 8 64 7 7 3 7 The largest of these is . Now we compare with using Method II. 7 · 5 > 8 · 3; therefore, 8 8 5 8 21 42 = 32 64 3 5 21 32 11 16 55 64 7 8 is the greatest fraction. www.petersons.com 30 Chapter 2 Exercise 5 Work out each problem. Circle the letter that appears before your answer. 1. Arrange these fractions in order of size, from largest to smallest: (A) (B) (C) (D) (E) 2. 4 21 ,, 15 5 3 4 12 ,, 15 3 5 21 4 ,, 5 3 15 142 ,, 3 15 5 12 4 ,, 3 5 15 4 21 ,,. 15 5 3 4. Which of the following fractions is closest to (A) (B) (C) (D) (E) 1 2 7 12 5 6 11 12 19 24 3 ? 4 5. Which of the following fractions is closest to (A) (B) (C) (D) (E) 5 12 8 15 11 20 31 60 7 15 1 ? 2 Which of the following fractions is the smallest? (A) (B) (C) (D) (E) 3 4 5 6 7 8 19 24 13 15 3 5 7 10 5 8 3 4 13 20 3. Which of the following fractions is the largest? (A) (B) (C) (D) (E) www.petersons.com Operations with Fractions 31 6. COMPLEX FRACTIONS To simplify complex fractions, fractions that contain fractions within them, multiply every term by the smallest number needed to clear all f...
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This note was uploaded on 08/15/2010 for the course MATH a4d4 taught by Professor Colon during the Spring '10 term at Embry-Riddle FL/AZ.

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