COURSE 3 LESSON 4-3 Comparing and Ordering Rational Numbers Which is greater, 5 or 6 ? 9 11 Rewrite each fraction with the denominator 9 • 11 = 99. 5 5 • 11 = 9 9 • 11 Multiply the numerator and denominator by 11. 55 Multiply. = 99 6 6•9 = 11 11 • 9 Multiply the numerator and denominator by 9. 54 = 99 55 Multiply. 54 5 6 Since 99 > 99 , 9 > 11 . 4-3 COURSE 3 LESSON 4-3 Comparing and Ordering Rational Numbers Which is greater, 7 or 5 ? 18 Multiples of 18: 18, 36 Multiples of 12: 12, 24, 36 12 List multiples of each denominator to find their LCD. Since the LCM of 18 and 12 is 36, the LCD of the fractions is 36. 7 7•2 = 18 18 • 2 14 = 36 Multiply the numerator and denominator by 2. Simplify. 4-3 COURSE 3 LESSON 4-3 Comparing and Ordering Rational Numbers (continued) 5 5•3 = 12 12 • 3 Multiply the numerator and denominator by 3. 15 = 36 15 Simplify. 14 5 7 Since 36 > 36 , 12 > 18 . 4-3 COURSE 3 LESSON 4-3 Comparing and Ordering Rational Numbers The Eagles won 7 out of 11 games while the Seals won 8 out of 12 games. Which team has the better record? Change each fraction to a decimal. Compare the two decimals. 7 Eagles: 11 8 Seals: 12 0.636363 Divide. Use a calculator. 0.666667 Since 0.666 > 0.636, the Seals have the better record. 4-3 COURSE 3 LESSON 4-3 Comparing and Ordering Rational Numbers Order –0.175, 2 , – 5 , 1.7, –0.95 from least to greatest. 3 8 Write each fraction as a decimal. 2 3 – 0.667 5 = –0.625 8 Then graph each decimal on a number line. The order of the points from left to right gives the order of the numbers from least to greatest. –0.95 < –0.625 < –0.175 < 0.667 < 1.7 So, –0.95 < 5 –8 < –0.175 < 2 3 4-3 < 1.7. COURSE 3 LESSON 4-3 Comparing and Ordering Rational Numbers Compare. Use <, >, or =. 1. 5 < 3. 15 = 12 50 8 15 2. 4 > 36 120 4. 7 = 0.35 5 20 8 11 5. Order 0.17, 1 , –0.3, 0, and – 1 from least to greatest. 5 4 –0.3, – 1 , 0, 0.17, 1 4 5 4-3