Question 1

Which of the following is NOT included in the five-number summary for a data set?

Accepted Answer

Mean

Question 2

Given the data set: 56, 67, 68, 72, 74, 75, 88, 90, 97, 99, what is the value of the first quartile ($Q_1$)?

Accepted Answer

$Q_1 = 68$

Question 3

What is the formula for sample variance ($s^2$) for a data set with $n$ observations?

Accepted Answer

$s^2 = \frac{\sum_{i=1}^{n} (x_i - \bar{x})^2}{n-1}$

Question 4

If the interquartile range (IQR) for a data set is 22, which of the following is the correct calculation?

Accepted Answer

$IQR = Q_3 - Q_1$

Question 5

A business analyst uses StatCrunch to find the mean of a data set. Which formula does StatCrunch use to calculate the mean?

Accepted Answer

$\bar{x} = \frac{\sum_{i=1}^{n} x_i}{n}$

Question 6

Which statistic is most appropriate for identifying the center of a skewed distribution?

Accepted Answer

Median

Question 7

In StatCrunch, which step is necessary to select multiple statistics (such as mean, variance, and mode) at once?

Accepted Answer

Hold Ctrl and click each statistic

Question 8

Given the data set: 56, 67, 68, 72, 74, 75, 88, 90, 97, 99, what is the sample standard deviation?

Accepted Answer

$s = 14.275096$

Question 9

Which of the following best describes the mode for the given data set: 56, 67, 68, 72, 74, 75, 88, 90, 97, 99?

Accepted Answer

No mode

Question 10

A manager wants to summarize employee performance scores using the five-number summary. Which statistics will be included?

Accepted Answer

Minimum, $Q_1$, Median, $Q_3$, Maximum

Question 11

If a data set has a sample variance of $200.93133$, what is the sample standard deviation?

Accepted Answer

$s = \sqrt{200.93133}$

Question 12

Which of the following is a correct interpretation of the interquartile range (IQR) in business statistics?

Accepted Answer

It measures the spread of the middle 50% of the data.

Question 13

A company wants to compare the variability of two departments' scores. Which statistic should they use?

Accepted Answer

Standard deviation

Question 14

Which step in StatCrunch allows you to change the data column or statistics being calculated after computation?

Accepted Answer

Use the Options button

Question 15

If the median of a data set is 74.5, what does this indicate about the data?

Accepted Answer

Half the data values are less than or equal to 74.5, and half are greater than or equal to 74.5.

Question 16

Which of the following is the correct formula for the interquartile range (IQR)?

Accepted Answer

$IQR = Q_3 - Q_1$

Question 17

A business analyst finds that the minimum value in a data set is 56 and the maximum is 99. What is the range?

Accepted Answer

$	ext{Range} = 99 - 56 = 43$

Question 18

Which of the following is NOT a measure of central tendency?

Accepted Answer

Variance

Question 19

If a data set has no repeated values, what is the mode?

Accepted Answer

No mode

Question 20

Which summary statistic is most affected by extreme values in a data set?

Accepted Answer

Mean

Descriptive Statistics Using StatCrunch: Five-Number Summary, Mean, Variance, and Standard Deviation

Study Guide - Practice Questions