Ap Statistics Semester Exam Review Worksheets With Answer Key (Page 7 of 9) in pdf

Ap Statistics Semester Exam Review Worksheets With Answer Key Page 7

In the following probability distribution, X = the number of 10s rolled on three ten-sided dice. Use it to answer

questions #63-65.

P(X)

.729

.243

.027

.001

63. Is the distribution above discrete or continuous?

64. Find the mean and standard deviation of X.

65. If you multiplied each X-value above by 3 and added 5, what would be the new mean and standard

deviation of X?

66. A man on the street offers you a wager. He’ll fan out a deck of cards and let you pick one at random. If

it’s a face card, he’ll give you $2. If it’s an ace, he’ll give you $4. If it’s anything else, you give him $1.

What is the amount you are expected to win each time you play? Should you take his offer?

Chapter Eight:

67. For each of the following situations, say whether or not a binomial distribution could be used:

a. You draw three cards out of deck, without replacing them. Let X be the number of red cards

drawn.

b. You survey a SRS of 100 college students. Let X be the number of them that are over 21.

c. You roll a die twenty times. Let X be the number of times you roll a prime number.

d. You spin a spinner ten times. Let X be the total sum of the numbers you roll.

You will roll a twenty-sided die ten times in a row, and you will record the number of times you roll a perfect

square. Use this situation to answer questions #68-72.

68. What is the probability that you roll a perfect square exactly 4 times?

69. What is the probability that you roll a perfect square no more than 2 times?

70. What is the probability that you roll a perfect square at least 6 times?

71. How many times should you expect to roll a perfect square?

72. Can you use a normal curve to approximate this distribution? Why or why not?

You want to know how many women in Ohio are democrats. You will interview 200 women and ask them

their political party. Imagine that, in reality, 58% of Ohio women are democrats. Use this information to

answer questions #73-75.

73. Strictly speaking, this situation isn’t binomial, because the 200 trials aren’t technically independent.

Why can we still use a binomial distribution to calculate probabilities here?

74. What is the mean and standard deviation of the number of democrats in your sample?

75. Use a normal curve to approximate the probability that at least 130 women in your sample are

democrats.

Ap Statistics Semester Exam Review Worksheets With Answer Key Page 7