Table of Contents Number and Operation Lesson 1 IIII Minutes to IV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Prime and Composite Numbers Lesson 2 Gateway to America . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Exponents Lesson 3 Looking at Lepidoptera . . . . . . . . . . . . . . . . . . . . . . . 17 Order of Operations Lesson 4 A Perfect 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 LCM and GCF Lesson 5 A Sticky Situation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Division with Fractions Lesson 6A Tale of No Tails . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Multiply with Decimals Lesson 7Happy Centennial! . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Fractions, Decimals, and Percents Geometry Lesson 8M.C. Escher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Angle Sums Lesson 9 Sue’s Discovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Translations Lesson 10Flag Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Central Angles Measurement Lesson 11 La Alhambra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Area of a Parallelogram Ancient Wonder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Area of a Triangle Lesson 13 Big Ben . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Circumference Lesson 14Leaning Tower of Pisa . . . . . . . . . . . . . . . . . . . . . . . 83 Area of a Circle © 2005 Options Publishing Lesson 12 Algebra Lesson 15 Football Frenzy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 Add Integers Lesson 16Underwater World . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Subtract Integers Lesson 17 The United Nations . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Translate Verbal Expressions Lesson 18 Aesop’s Fables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Solve 1-Step Equations Lesson 19 Read All About It! . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Ratio and Proportion Data Analysis and Probability Lesson 20 The 8th Wonder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 Circle Graphs Lesson 21The Stanley Cup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Measures of Central Tendency Lesson 22Lewis, Clark, and Company . . . . . . . . . . . . . . . . . . 131 Probability of Independent Events Math Tools Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Order of Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 Sieve of Eratosthenes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 1 © 2005 Options Publishing Perimeter and Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 Geometric Figures and Polygons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 Fractions, Decimals, and Percents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Prime and Composite Numbers 1 IIII Minutes to IV In ancient Rome, capital letters were used to represent numbers. These letters—I, V, X, L, C, D, and M—are known today as Roman numerals. In Roman numerals, the number 4 is written IV. But on many clock faces, the number 4 is represented by IIII. Why? There are many theories. Some people believe that IIII is used on many clock faces because IV is not wide enough—it would make the clock face look unbalanced. Others say that the use of IIII came before the use of IV, and it was never changed on clocks. Whatever the reason, on many clock faces today, you will still see IIII instead of IV. Get Started One way to express a number is as a product of factors. Express the numbers below as different products of factors. Then list all the factors. 6 11 6 1 6 © 2005 Options Publishing 6 2 3 Factors: 1, 2, 3, 6 Factors: Factors: 12 15 Factors: Lesson 1: Prime and Composite Numbers 5 Working with Prime and Composite Numbers You can use what you know about factors to learn about prime numbers and composite numbers. •If a number has only two different factors, one and itself, it is a prime number. For example, 5 is a prime number because its only factors are 1 and 5: 515 •If a number has more than two different factors, it is a composite number. For example, 8 is a composite number because its factors are 1, 2, 4, and 8: 818 824 •The number 1 is neither prime nor composite. It has only one factor: 111 Complete the table below. Decide whether each number is prime or composite. Number 1. 2. 9 1 9, 3 3 Factors Prime or Composite 1, 3, 9 Composite 13 15 © 2005 Options Publishing 3. Products 6 Level F Practice Write prime or composite to describe each number below. Show your work. Number 4. 5. 6. 7. 8. 9. Products Factors Prime or Composite 21 40 18 19 29 33 It’s a Fact! Solve a Problem 10. How many prime numbers are there between 1 and 25? List them and explain how you found your answer. © 2005 Options Publishing A horizontal line over a Roman numeral meant to multiply that number by 1,000. So the Roman numeral above represents the number 5,000. Lesson 1: Prime and Composite Numbers 7 Finding Prime and Composite Numbers A method called the Sieve of Eratosthenes can be used to find prime numbers less than a given number. Use the steps below to find the prime numbers less than 36. STEP 2 Start with 2, which is the first prime number. Circle 2. Cross out every second number after 2, because these are multiples of 2. STEP 3 Find the next number that is not crossed out. This number, 3, is the next prime number. Circle 3. Cross out all the other multiples of 3. Some numbers may already be crossed out. STEP 4 Find the next number that is not crossed out. This number, 5, is the next prime number. Circle 5. Cross out all the other multiples of 5. 2 3 4 5 Level F 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 Continue this pattern until all the prime numbers are circled. 8 6 © 2005 Options Publishing STEP 1 List whole numbers between 1 and 36 in order. Use a chart like the one at the right. Show What You Know Use the number chart below and the steps you learned to find all the prime numbers less than 50. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 1.List the prime numbers less than 50: 2.How would you describe the numbers that are crossed out in the chart? Explain your answer. © 2005 Options Publishing 3.Is 57 a prime number? Use the number chart above and the steps you learned to find out. On Your Own On Your Own Continue the activity above to find the prime numbers less than 100. List all the prime ­numbers less than 100. Lesson 1: Prime and Composite Numbers 9 1 Test Yourself 1. Which shows all the factors of 8? 1, 2, 4 1, 8 1, 8, 16 1, 2, 4, 8 5. How many prime numbers are there between 20 and 30? Explain your answer. 2. What do we call a number that has only two different factors? composite number odd number 6. A. List all the factors of 55. prime number B. How many factors does 55 have? even number 3. Which of the numbers below is a prime number? C. Is 55 prime or composite? 15 37 51 91 7. Think Back Explain in your own words what a factor is. Explain what a multiple is. 19 29 47 51 10 Level F © 2005 Options Publishing 4. Which of the numbers below is a composite number?