Question 1

Given the distribution shown in the first image, which labeled point (A, B, or C) corresponds to the mean, median, and mode of the distribution?

Accepted Answer

A = mode, B = median, C = mean

Question 2

Using the table of Bachelor's degrees conferred by a university (second image), what is the probability that a randomly selected student majored in Physics or Philosophy? Round your answer to three decimal places.

Accepted Answer

$$0.472$$

Question 3

Refer to the customer satisfaction table (third image). What is the probability that a randomly selected respondent did NOT have a low level of satisfaction with the company? Round to the nearest hundredth.

Accepted Answer

$$0.97$$

Question 4

Which measure of central tendency is NOT resistant to extreme values in a numeric data set?

Accepted Answer

Mean

Question 5

A bag contains 6 red marbles, 3 blue marbles, and 5 green marbles. If a marble is randomly selected, what is the probability that it is blue? Express your answer as a simplified fraction.

Accepted Answer

$$\frac{1}{4}$$

Question 6

A student receives test scores of 62, 83, and 91. The term project score is 88 and the homework score is 76. Each test is worth 20% of the final grade, the term project is 25%, and the homework is 15%. What is the student's mean score in the class?

Accepted Answer

$$80.6$$

Question 7

If the mean age of a group is 74.0 and the standard deviation is 9.7, what percentage of the respondents will be between 64.3 and 93.4 years old, assuming a bell-shaped distribution?

Accepted Answer

$$81.5\%$$

Question 8

Which of the following cannot be a probability?

Accepted Answer

$$-0.2$$

Question 9

A motel has a policy of booking as many as 150 guests in a building that holds 140. If only 85% of booked guests show up, what is the probability that not enough rooms will be available? (Use the binomial distribution and round to four decimal places.)

Accepted Answer

$$0.0005$$

Question 10

A bag contains 10 white, 12 blue, 13 red, 7 yellow, and 8 green balls. If two balls are selected with replacement, what is the probability that both are red? Round to the nearest ten-thousandth.

Accepted Answer

$$0.0676$$

Question 11

Which is better: a score of 82 on a test with a mean of 70 and a standard deviation of 8, or a score of 82 on a test with a mean of 75 and a standard deviation of 4?

Accepted Answer

The second 82

Question 12

If $$P(A) = 0.45$$, $$P(B) = 0.25$$, and $$P(B|A) = 0.45$$, are A and B independent?

Accepted Answer

No

Question 13

A student scores 92 on a test with a mean of 71 and a standard deviation of 15, and 688 on a test with a mean of 493 and a standard deviation of 150. Which score corresponds to the higher relative position?

Accepted Answer

Score of 92

Question 14

What is the z-score for the value 96, when the mean is 92 and the standard deviation is 3?

Accepted Answer

$$z = 1.33$$

Question 15

Which of the following is the easiest measure of dispersion to calculate?

Accepted Answer

Range

Question 16

A game has three outcomes: win (0.4), tie (0.5), and loss (0.1). What is the probability of NOT winning in a single play?

Accepted Answer

$$0.6$$

Question 17

Which of the following random variables is discrete?

Accepted Answer

The number of pills in an aspirin bottle

Question 18

A bag contains 10 white, 12 blue, 13 red, 7 yellow, and 8 green balls. If two balls are selected without replacement, what is the probability that both are blue? Round your answer to four decimal places.

Accepted Answer

$$0.0539$$

Question 19

A recent survey found that 79% of all adults over 50 wear sunglasses for driving. In a random sample of 80 adults over 50, what is the mean and standard deviation of those that wear sunglasses?

Accepted Answer

Mean: $$63.2$$, Standard deviation: $$3.64$$

Statistics Study Guide: Measures of Central Tendency, Probability, and Data Interpretation

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