Week in Review # 9 MATH 365 Marcia Drost c 5.1 - 5.2 Drost, 2005 Created and complied by Sherry Scarborough with thanks for additional problems from Zach Barcevac, Lynnette Cardenas, Greg Klein, David Manuel, Jane Schielack, and Jenn Whitfield. 1. True or False: The set closed under addition. −2 2 , 0, 3 3 9 26 c. 8 25 d. 7 24 a. 000000000000 111111111111 111111111111 000000000000 000000000000 111111111111 000000000000 111111111111 000000000000 111111111111 000000000000 111111111111 000000000000 111111111111 000000000000 111111111111 000000000000 111111111111 is 2. Circle which fractions are less than onethird. 10 a. 27 b. 7. Given that the entire shape represents one unit area, write a fraction in lowest terms that represents the shaded portion. b. 0000000111111 1111111 0000001111111 111111 0000000 1111111 1111111 0000000 000000 0000000 0000000 1111111 000000 111111 0000000 1111111 0000000 1111111 000000 0000000 0000000111111 1111111 0000001111111 111111 0000000 1111111 0000000111111 1111111 0000001111111 111111 0000000 1111111 1111111 0000000 000000 0000000 0000000 1111111 000000 0000000 0000000111111 1111111 0000001111111 111111 0000000 1111111 0000000 1111111 000000 111111 0000000 1111111 8. Find three rational numbers in fraction −4 −5 and . form that are between 9 9 9. What is the name of the property that guarantees that between any two distinct rational numbers is a rational number? 5 by shading 6 a. congruent rectangles 10. Represent 3. Put the following fractions in order from 25 −9 5 4 , , , smallest to largest: 16 10 11 7 b. unit segments 2 4. Find two rational numbers between 7 3 and . 7 5. Give an example of the Fundamental Law of Fractions. 6. Circle the properties that hold for subtraction of rational numbers. closure commutative associative c. congruent circles d. by shading congruent sectors (pieshaped pieces) of a circle. 11. Give an example of a rational number 20. Circle all values which are equivalent to 9 that is: . 4 a. a proper fraction 2 a. 3 b. an improper fraction c. a fraction that is equivalent to an integer b. 2 d. a fraction in simplest form or lowest terms c. 18 8 d. −27 12 1 4 e. a fraction not in lowest terms 12. Simplify: 28 7 5 + − = a. 36 45 10 6 2 9 b. − + = x 2x + 2 (x + 1)2 5 21. Find the additive inverse of 4 as an im6 proper fraction in lowest terms. 105 22. How did the early Egyptians write the to a mixed number in lowest 13. Change following numbers: 39 terms. 5 a. 6 2 14. Change −7 to a fraction of the form 11 a 3 where a and b are integers, such that b. b 4 b 6= 0. Show your work and do not just use a rule or property. 5 c. 8 15. Using drawings and shadings of sectors of 1 2 circles, model 2 + 1 and give its sum. 2 5 23. Give an example of how the ancient Babylonian use of fractions is still in use t v 16. If , ∈ Q, then by definition of subtoday. u w t v traction, − = d if, and only if, what? u w 24. True or false: Given two positive rational 17. Use the definition of less than to prove −5 −2 < . 7 5 numbers, the one with the largest numerator is the largest. 18. A bread recipe requires 6 23 cups of flour. 25. True or false: Given two positive rational numbers, the one with the greatest Courtney put 3 14 cups of flour into the denominator is the least. bread batter. How much more flour does she need to put into the batter? Write an expression that describes this problem 26. True or false: Given two rational numa c a c and then simplify it to find the answer. bers, and , then < if a · d < b · c. b d b d 1 1 19. Model + . 3 4