C Challenge

32. Manufacturing Tubs of yogurt weigh 1.0 lb each, with a standard deviation of 0.06 lb. At a quality control checkpoint, 12 of the tubs taken as samples weighed less than 0.88 lb. Assume that the weights of the samples were normally distributed. How many tubs of yogurt were taken as samples?
33. Reasoning Describe how you can use a normal distribution to approximate a binomial distribution. Draw a binomial histogram and a normal curve to help with your explanation.

Standardized Test Prep

SAT/ACT

34. For a daily airline flight between two cities, the number of pieces of checked luggage has a mean of 380 and a standard deviation of 20. On what percent of the flights would you expect from 340 to 420 pieces of checked luggage?
    1. 34%
    2. 47.5%
    3. 68%
    4. 95%
35. A jar contains 37 pennies, 53 nickels, 29 dimes, and 21 quarters. A coin is drawn at random from the jar. What is the probability that the coin drawn is NOT a quarter?
    6. 56 , 869 2 , 744 , 000 fraction 56 comma 869 , over 2 comma 744 comma 000 end fraction
    7. 3 20 3 twentieths
    8. 3 17 3 seventeenths
    9. 17 20 17 over 20
36. A multiple-choice quiz contains five questions, each with three answer choices. You select all five answer choices at random. What is the best estimate of the probability that you will get at least four answers correct?
    1. 4.1%
    2. 4.5%
    3. 13.2%
    4. 46.1%

Short Response

37. Distribution A has 50 data values with mean 40 and standard deviation 2.4. Distribution B has 30 data values with mean 40 and standard deviation 2.8. Which distribution has more data values at or below 40? Show your work.

Mixed Review

See Lesson 11-8.

Find the probability of x successes in n trials for the given probability of success p on each trial.

38. x = 4 , n = 7 , p = 0.2 x equals 4 comma n equals 7 comma p equals 0.2
39. x = 2 , n = 9 , p = 0.4 x equals 2 comma n equals 9 comma p equals 0.4
40. x = 6 , n = 10 , p = 0.3 x equals 6 comma n equals 10 comma p equals 0.3

See Lesson 10-1.

Graph each equation. Identify the conic section and describe the graph and its lines of symmetry. Then find the domain and range.

41. x 2 + y 2 = 64 x squared , plus , y squared , equals 64
42. x 2 − y 2 = 9 x squared , minus , y squared , equals 9
43. 9 x 2 + 25 y 2 = 225 9 x squared , plus 25 , y squared , equals 225

Get Ready! To prepare for Lesson 12-1, do Exercises 44–46.

See Lesson 2-6.

Write an equation for each horizontal translation of y = x − 2 . y equals x minus 2 .  Then graph each translation.

44. 1 unit right
45. 2 units left
46. 3 4 3 fourths  unit left

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