Q: A boxplot shows a data set with Q1 = 20, Q3 = 40, and a maximum value of 70. According to the 1.5(IQR) rule, is 70 an outlier?

Yes, because $$70 \u003e Q3 + 1.5 \times (Q3 - Q1)$$

Question 1

Which of the following best describes a variable that can only take on values such as 0, 1, 2, 3, and cannot take on decimal values?

Accepted Answer

A discrete quantitative variable

Question 2

A researcher collects the heights (in centimeters) of 100 students. Which type of variable is height?

Accepted Answer

Continuous quantitative

Question 3

Given the following frequency table for M&M’s colors: Green (12), Blue (12), Orange (10), Red (8), Yellow (8), Brown (7), what is the relative frequency (proportion) of Orange M&Ms? (Total = 57)

Accepted Answer

$$0.18$$

Question 4

Which graphical summary is most precise for comparing categories with similar relative frequencies?

Accepted Answer

Bar graph

Question 5

A histogram is most appropriate for which type of data?

Accepted Answer

Quantitative data

Question 6

Refer to the first image. Which distribution is right-skewed, and what does this imply about the mean and median?

Accepted Answer

Income; mean \u003e median

Question 7

Given a data set with a mean of $$50$$ and a standard deviation of $$10$$, what interval contains approximately 95% of the data according to the Empirical Rule?

Accepted Answer

$$[30, 70]$$

Question 8

Which of the following is a resistant measure of center?

Accepted Answer

Median

Question 9

A student’s SAT math score is 700. The mean is 500 and the standard deviation is 100. What is the z-score for this student?

Accepted Answer

$$z = 2$$

Question 10

Which of the following statements is true about the interquartile range (IQR)?

Accepted Answer

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

Question 11

If a distribution is left-skewed, which of the following is most likely true?

Accepted Answer

Mean \u003c Median

Question 12

A boxplot shows a data set with Q1 = 20, Q3 = 40, and a maximum value of 70. According to the 1.5(IQR) rule, is 70 an outlier?

Accepted Answer

Yes, because $$70 \u003e Q3 + 1.5 	imes (Q3 - Q1)$$

Question 13

Which of the following is NOT a property of the standard deviation?

Accepted Answer

It is resistant to outliers

Question 14

A time plot is most useful for which type of data?

Accepted Answer

Data collected over time (time series)

Question 15

If the mean and median of a data set are equal, which of the following is most likely true about the distribution?

Accepted Answer

It is symmetric

Question 16

Which of the following best describes the mode?

Accepted Answer

The value that occurs most frequently

Question 17

Given a data set: 2, 4, 4, 5, 7, 16. What is the variance?

Accepted Answer

$$29.2$$

Question 18

Which of the following is true about a Pareto chart?

Accepted Answer

It is a bar graph with categories ordered by frequency

Question 19

If a value has a z-score of 3.5 in a bell-shaped distribution, what can you conclude?

Accepted Answer

It is likely an outlier

Question 20

Which of the following is the correct formula for the sample standard deviation $$s$$?

Accepted Answer

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

Descriptive Statistics: Types, Graphs, Measures of Center and Variability

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