Master 4.27 Extra Practice 1 Lesson 1: Numbers in the Media 1. Rewrite each number in standard form. a) 3.6 million 3 b) 6 billion 4 c) 1 million 2 1 d) 2 billion 10 e) 4.25 million f) 1.4 billion 2. Use decimals. Round each number to the nearest hundredth of a million. a) 16 284 371 b) 1 906 242 c) 47 072 148 d) 4 575 234 e) 51 421 357 f) 5 393 175 Lesson 2: Exploring Thousandths 1. Write each number as a decimal. 291 a) 1000 3 d) 19 100 173 b) 4 1000 17 e) 1000 8 c) 6 1000 6 f) 4 10 2. Write each decimal as a fraction or a mixed number. a) 0.436 b) 5.016 c) 13.004 d) 10.102 e) 7.019 f) 4.3
Master 4.28 Extra Practice 2 Lesson 3: Comparing and Ordering Decimals 1. Use >, <, or =. a) 2.537 2.58 b) 0.607 0.601 c) 1.42 1.413 d) 2.6 2.600 2. Order the numbers from greatest to least. a) 0.439, 1.004, 0.37 b) 2.83, 1.9, 0.297 c) 6.237, 6.019, 6.284 d) 3.105, 3.6, 5.12 3. Write a number between 2.358 and 2.361. Lesson 4: Rounding Decimals 1. Round to the nearest whole number. a) 3.764 b) 0.635 c) 7.014 d) 2.535 e) 1.862 f) 17.412 g) 3.5 h) 6.28 2. Round to the nearest tenth. a) 8.64 b) 7.235 c) 0.062 d) 7.317 e) 17.68 f) 145.25 g) 1.423 h) 8.004 3. Round to the nearest hundredth. a) 3.456 b) 7.318 c) 6.994 d) 33.333 e) 18.024 f) 2.587 g) 0.328 h) 1.451
Master 4.29 Extra Practice 3 Lesson 5: Estimating Sums and Differences 1. Estimate each sum. a) 8.1 + 7.2 b) 6.51 + 4.03 c) 7.358 + 2.71 d) 4.758 + 3.164 e) 0.943 + 0.995 f) 3.568 + 2.541 2. Estimate each difference. a) 26.18 20.92 b) 5.384 2.111 c) 8.43 2.251 d) 2.205 0.973 e) 6.275 1.184 f) 7.042 3.962 Lesson 6: Adding and Subtracting Decimals 1. Add. a) 1.685 b) 5.148 c) 0.387 d) 51.239 + 4.937 + 3.227 + 4.996 + 8.468 2. Subtract. a) 13.352 b) 5.891 c) 11.026 d) 9.405 7.166 1.309 6.382 3.881 3. Write vertically, then add or subtract. a) 6.941 2.34 b) 3.85 + 7.206 c) 1.456 + 0.937 d) 8.142 + 0.51 e) 2.856 1.23 f) 5.34 1.9
Master 4.30 Extra Practice 4 Lesson 7: Multiplying Decimals by 10, 100, 1000, 10 000 Use mental math to find each product. 1. a) 4.9 10 b) 27.631 10 c) 0.937 10 4.9 100 27.631 100 0.937 100 4.9 1000 27.631 1000 0.937 1000 2. a) 5.63 10 b) 7.851 10 000 c) 0.682 100 d) 59.042 100 e) 17.384 1000 f) 20.89 1000 g) 94.007 10 000 h) 26.34 100 i) 8.005 10 3. A certain seed has a mass of 0.763 g. What is the total mass of 10 of these seeds? 100 seeds? 1000 seeds? 10 000 seeds? Lesson 8: Dividing Decimals by 10, 100, 1000, 10 000 Use mental math to find each quotient. 1. a) 4.5 10 b) 7.62 10 c) 0.974 10 4.5 100 7.62 100 0.974 100 4.5 1000 7.62 1000 0.974 1000 2. a) 6 10 b) 7.4 1000 c) 3.497 100 d) 5.8 100 e) 17 10 000 f) 143.946 1000 3. One thousand new pennies have a mass of 2350 g. What is the mass of one penny? 4. One hundred new 50-cent coins have a mass of 690 g. What is the mass of one 50-cent coin?
Master 4.31 Extra Practice 5 Lesson 9: Multiplying Whole Numbers by 0.1, 0.01, 0.001 Use mental math to find each product. 1. a) 25 0.1 b) 4 0.1 c) 145 0.1 25 0.01 4 0.01 145 0.01 25 0.001 4 0.001 145 0.001 2. a) 3 0.01 b) 7 0.1 c) 18 0.001 d) 58 0.1 e) 136 0.001 f) 1568 0.01 3. Use mental math. a) 5 0.1 b) 16 0.01 c) 127 0.001 5 10 16 100 127 1000 Lesson 10: Multiplying Decimals by a 1-Digit Whole Number 1. Multiply. a) 5.04 b) 6.384 c) 17.009 7 2 6 d) $17.35 e) 1.257 f) 0.738 8 3 9 2. Write vertically, then multiply. a) 3.456 4 b) 0.509 5 c) 7.382 7 d) $1.89 8 e) 2.049 6 f) 1.158 3
Master 4.32 Extra Practice 6 Lesson 11: Dividing Decimals by a 1-Digit Whole Number 1. Estimate. Then divide. a) 3.472 4 b) 7.535 5 c) 9 2 d) 0.936 3 e) 0.006 6 f) 8.239 7 2. Divide. Multiply to check your answers. a) 8 0.848 b) 6 2.466 c) 3 7.41 d) 9 1.836 e) 5 46 f) 2 9.434 3. Said paid $1.71 for a package of 9 pencils. How much did each pencil cost? Lesson 12: Dividing Decimals 1. Estimate first. Then divide until the remainder is 0. a) 3.589 2 b) 18 4 c) 2.768 5 d) 14.07 5 e) 49.77 2 f) 13 5 2. Divide. Round each quotient to the same number of decimal places as there are in the dividend. a) 3.189 2 b) 5.1 9 c) $2.05 2 d) 27 4 e) 7.684 3 f) 13 6 3. Each mini van holds 9 people. How many mini vans are needed for 76 people?
Master 4.33a Sample Answers Extra Practice 1 Master 4.27 Lesson 1 1. a) 3 600 000 b) 6 750 000 000 c) 500 000 d) 2 100 000 000 e) 4 250 000 f) 1 400 000 000 2. a) 16.28 million b) 1.91 million c) 47.07 million d) 4.58 million e) 51.42 million f) 5.39 million Lesson 2 1. a) 0.291 b) 4.173 c) 6.008 d) 19.03 e) 0.017 f) 4.6 436 16 4 2. a) 1000 b) 5 1000 c) 13 1000 102 19 3 d) 10 1000 e) 7 1000 f) 4 10 Extra Practice 2 Master 4.28 Lesson 3 1. a) 2.537 < 2.58 b) 0.607 > 0.601 c) 1.42 > 1.413 d) 2.6 = 2.600 2. a) 1.004, 0.439, 0.37 b) 2.83, 1.9, 0.297 c) 6.284, 6.237, 6.019 d) 5.12, 3.6, 3.105 3. 2.360 Lesson 4 1. a) 4 b) 1 c) 7 d) 3 e) 2 f) 17 g) 4 h) 6 2. a) 8.6 b) 7.2 c) 0.1 d) 7.3 e) 17.7 f) 145.3 g) 1.4 h) 8.0 3. a) 3.46 b) 7.32 c) 6.99 d) 33.33 e) 18.02 f) 2.59 g) 0.33 h) 1.45 Extra Practice 3 Master 4.29 Lesson 5 1. a) About 15 b) About 10.5 c) About 10 d) About 8 e) About 2 f) About 6 2. a) About 5 b) About 3 c) About 6 d) About 1 e) About 5 f) About 3 Lesson 6 1. a) 6.622 b) 8.375 c) 5.383 d) 59.707 2. a) 6.186 b) 4.582 c) 4.644 d) 5.524 3. a) 6.941 b) 3.850 c) 1.456 2.340 + 7.206 + 0.937 4.601 11.056 2.393 d) 8.142 e) 2.856 f) 5.34 + 0.510 1.230 1.90 8.652 1.626 3.44 Extra Practice 4 Master 4.30 Lesson 7 1. a) 49, 490, 4900 b) 276.31, 2763.1, 27 631 c) 9.37, 93.7, 937 2. a) 56.3 b) 78 510 c) 68.2 d) 5904.2 e) 17 384 f) 20 890 g) 940 070 h) 2634 i) 80.05 3. 7.63 g, 76.3 g, 763 g, 7630 g Lesson 8 1. a) 0.45, 0.045, 0.0045 b) 0.762, 0.0762, 0.007 62 c) 0.0974, 0.009 74, 0.000 974 2. a) 0.6 b) 0.0074 c) 0.034 97 d) 0.058 e) 0.0017 f) 0.143 946 3. 2.35 g 4. 6.9 g
Master 4.33b Sample Answers continued Extra Practice 5 Master 4.31 Lesson 9 1. a) 2.5, 0.25, 0.025 b) 0.4, 0.04, 0.004 c) 14.5, 1.45, 0.145 2. a) 0.03 b) 0.7 c) 0.018 d) 5.8 e) 0.136 f) 15.68 3. a) 0.5, 0.5 b) 0.16, 0.16 c) 0.127, 0.127 Lesson 10 1. a) 35.28 b) 12.768 c) 102.054 d) $138.80 e) 3.771 f) 6.642 2. a) 13.824 b) 2.545 c) 51.674 d) $15.12 e) 12.294 f) 3.474 Extra Practice 6 Master 4.32 Lesson 11 1. a) A little less than 1; 0.868 b) About 1.5; 1.507 c) A little more than 4; 4.5 d) About 0.3; 0.312 e) About 0.001; 0.001 f) A little more than 1; 1.177 2. a) 0.106; 0.106 8 = 0.848 b) 0.411; 0.411 6 = 2.466 c) 2.47; 2.47 3 = 7.41 d) 0.204; 0.204 9 = 1.836 e) 9.2; 9.2 5 = 46 f) 4.717; 4.717 2 = 9.434 3. $1.71 9 = $0.19; Each pencil cost 19 cents. Lesson 12 1. a) Less than 2; 1.7945 b) More than 4; 4.5 c) About 0.5; 0.5536 d) Almost 3; 2.814 e) About 25; 24.885 f) Less than 3; 2.6 2. a) 1.595 b) 0.6 c) $1.03 d) 7 e) 2.561 f) 2 3. 76 9 = 8.4; 9 vans are needed.