* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Comparing Integers
Survey
Document related concepts
Positional notation wikipedia , lookup
List of first-order theories wikipedia , lookup
Infinitesimal wikipedia , lookup
Large numbers wikipedia , lookup
Abuse of notation wikipedia , lookup
Factorization wikipedia , lookup
Collatz conjecture wikipedia , lookup
Division by zero wikipedia , lookup
P-adic number wikipedia , lookup
Transcript
Page 1 of 4 Comparing Integers BEFORE Now WHY? You compared and ordered fractions and decimals. You’ll compare and order integers. So you can order temperatures, as in Exercise 34. In the Real World Word Watch integer, p. 533 positive integer, p. 533 negative integer, p. 533 opposites, p. 534 Space Shuttles During a countdown for a shuttle launch, “T10 seconds” means 10 seconds after liftoff. What number represents “T10 seconds”? During a launch, each second can be assigned an integer. The following numbers are integers . . . . , 5, 4, 3, 2, 1, 0, 1, 2, 3, 4, 5, . . . Negative integers are integers that are less than 0. Positive integers are integers that are greater than 0. Zero is neither negative nor positive. Negative numbers 6 5 4 3 2 1 Positive numbers 0 1 2 3 4 5 6 The integer 5 is read “negative 5.” Integers are often used to represent real-world quantities. Words like profit, increase, and above often indicate a positive integer. Words like loss, decrease, and below indicate a negative integer. EXAMPLE 1 Using Integers Write the integer that represents the situation. a. The countdown for the space shuttle is at “T10 seconds.” ANSWER 10 seconds b. A withdrawal of $25 ANSWER $25 Your turn now 1. a $15 profit Write the integer that represents the situation. 2. a 9 point decrease Lesson 11.1 3. a loss of 5 yards Comparing Integers 533 Page 2 of 4 Opposites Numbers increase as you move from left to right on a number line. Two numbers are opposites if they are the same distance from 0 on a number line, but are on opposite sides of 0. EXAMPLE with 2 Identifying Opposites Find the opposite of 3. Reading The integer 3 is read as “negative 3” or as “the opposite of 3.” 3 units 3 2 3 units 1 0 1 2 3 ANSWER The opposite of 3 is 3. EXAMPLE 3 Comparing Integers Compare 8 and 5. 8 9 5 8 7 6 5 4 3 2 1 0 1 ANSWER Because 8 is to the left of 5 on the number line, 8 5. Your turn now Find the opposite of the integer. 5. 7 4. 8 6. 12 7. 0 Copy and complete the statement using < or >. 8. 2 _?_ 2 EXAMPLE 4 9. 0 _?_ 1 10. 4 _?_ 5 11. 8 _?_ 9 Ordering Integers Golf In a golf tournament, the player with the lowest score wins. The table shows the scores of several golfers (including the winner) in the 2001 Masters. Who won? Solution 16 14 20 16 12 8 5 4 0 4 0 4 Golfer David Duvall Shingo Katayama Jesper Parnevik Duffy Waldorf Tiger Woods Score 14 4 5 0 16 8 ANSWER Tiger Woods won the 2001 Masters with the lowest score of 16. 534 Chapter 11 Integers Page 3 of 4 INTERNET Exercises eWorkbook Plus CLASSZONE.COM More Practice, p. 718 Getting Ready to Practice Vocabulary Find the opposite of the integer. 2. 1 1. 9 3. 15 Copy and complete the statement using < or >. 4. 7 _?_ 0 5. 2 _?_ 6 6. 8 _?_ 9 Graph the integers on a number line. Then order the integers from least to greatest. 7. 3, 2, 7, 9, 0 8. 2, 5, 6, 10, 8 9. 9, 0, 2, 3, 5 10. Scuba Divers A scuba diver is 12 feet below sea level. A second scuba diver is 25 feet below sea level. Write integers to represent the divers’ positions relative to sea level. Practice and Problem Solving Write the integer that represents the situation. 11. 6 degrees below 0 12. an increase of 20 cm 13. 5 people join the Math Club 14. a loss of $3 15. a withdrawal of 25 dollars 16. 2 feet under water 17. In-line Skating In-line skates are on sale for $10 off, helmets are $5 off, and knee pads are $4 off. Use an integer to represent the change in price for each item. Find the opposite of the integer. with Example 1 2 3 4 Homework Exercises 11–17 18–21 22–29 30–34 Online Resources CLASSZONE.COM • More Examples • eTutorial Plus 18. 4 19. 8 20. 11 21. 0 Copy and complete the statement using < or >. 22. 3 _?_ 7 23. 6 _?_ 0 24. 0 _?_ 4 25. 5 _?_ 7 26. 9 _?_ 9 27. 1 _?_ 5 28. 11 _?_ 12 29. 10 _?_ 8 Order the integers from least to greatest. 30. 8, 2, 6, 7, 3 31. 8, 0, 5, 1, 1 32. 1, 4, 4, 9, 6 33. 0, 3, 9, 6, 6 Lesson 11.1 Comparing Integers 535 Page 4 of 4 34. Temperatures The table shows the average low temperature for each month in Big Delta, Alaska. Order the temperatures from least to greatest. Which month has the lowest average low temperature? Average Low Temperatures in Big Delta, Alaska Month Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. F 11 6 3 21 37 47 51 46 36 18 2 9 Number Sense Tell whether the statement is true or false. 35. The opposite of five is greater than negative four. 36. Zero is greater than negative seven. 37. The opposite of negative nine is less than ten. 38. Writing A number is sometimes less than its opposite. Use examples to explain this statement. 39. Challenge Two integers are opposites of each other. One integer is 7 units to the right of 5 on a number line. What are the two integers? Mixed Review Use a number line to add the numbers. (p. 688) 40. 5 4 41. 12 3 42. 8 2 Classify the solid. (Lesson 10.5) 43. 44. 45. Basic Skills Evaluate the expression when x 4.5 and y 1.23. 46. 6.07 x 47. x 2.58 48. y 10.9 Test-Taking Practice 49. Multiple Choice A 2-degree increase in temperature is represented by INTERNET which of the following? State Test Practice CLASSZONE.COM A. 20 B. 2 C. 2 D. 20 50. Multiple Choice If the integers 12, 4, 11, 12, 6, and 7 are put in order from least to greatest, which integer will be third in the list? F. 12 536 Chapter 11 Integers G. 4 H. 6 I. 12