Q: If a pie chart is constructed for the grades of students (A, B, C, D) with relative frequencies 0.15, 0.31, 0.39, and 0.15, what is the angle for grade C in the pie chart?

$$0.39 \times 360^\circ = 140.4^\circ$$

Question 1

Which of the following variables is quantitative and discrete?

Accepted Answer

The number of pet dogs sold in a pet shop

Question 2

A researcher records the number of crimes in 5 cities for the year 2015. This data is best classified as:

Accepted Answer

Cross-sectional data

Question 3

Which of the following is an example of a sample?

Accepted Answer

The mark scored by all 30 students of a class

Question 4

Given the following frequency distribution for daily distance (in km) walked by athletes: 0-2, 3-5, 6-8, 9-11, 12-14, what is the approximate class width?

Accepted Answer

$$3$$

Question 5

Which graphical method is most appropriate for displaying the distribution of a categorical variable such as car color?

Accepted Answer

Pareto chart

Question 6

A stem-and-leaf plot is constructed for the number of travelers to a national park. What is the main advantage of using a stem-and-leaf plot over a histogram?

Accepted Answer

It preserves the original data values

Question 7

If a pie chart is constructed for the grades of students (A, B, C, D) with relative frequencies 0.15, 0.31, 0.39, and 0.15, what is the angle for grade C in the pie chart?

Accepted Answer

$$0.39 	imes 360^\circ = 140.4^\circ$$

Question 8

Which of the following is NOT a correct step in constructing a frequency distribution for continuous data?

Accepted Answer

Using overlapping class intervals

Question 9

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

Accepted Answer

Small sets of discrete quantitative data

Question 10

Given the following data for the number of passengers in vehicles at a traffic light: 1, 2, 4, 5, 2, 1, 0, 1, 2, 0, 0, 1, 2, 3, 4, 5, 2, 1, 2, 0, 0, 1, 2, 3, 4, 2, 3, 4, 5, 2, 1, 1, 0, 1, 0, 1, 1, 0. What is the mode of the data?

Accepted Answer

$$1$$

Question 11

Which of the following best describes a time series data set?

Accepted Answer

Monthly sales for a car company in UAE for the year 2013

Question 12

If a frequency polygon is constructed from a frequency distribution, what is plotted on the x-axis?

Accepted Answer

Class midpoints

Question 13

Which of the following is a qualitative variable?

Accepted Answer

The major of students in a university

Question 14

A Pareto chart is used to:

Accepted Answer

Display categorical data in descending order of frequency

Question 15

If the frequency distribution for car colors in a parking lot is: White: 6, Green: 3, Black: 5, Silver: 2, Grey: 4, what is the relative frequency of Black cars?

Accepted Answer

$$\frac{5}{20} = 0.25$$

Question 16

Which of the following statements about histograms is TRUE?

Accepted Answer

They are used to display the distribution of continuous quantitative data

Question 17

In a frequency distribution, the cumulative frequency for a class is:

Accepted Answer

The sum of the frequencies for that class and all previous classes

Question 18

Which of the following is a correct formula for calculating the class midpoint ($$CM) $$given a class interval from $$a to$$ $$b$$?

Accepted Answer

$$CM = \frac{a + b}{2}$$

Question 19

A frequency polygon is constructed by plotting:

Accepted Answer

Frequencies at class midpoints and connecting them with straight lines

Question 20

Which of the following is a key difference between a histogram and a bar chart?

Accepted Answer

A histogram displays quantitative data with adjacent bars, while a bar chart displays categorical data with separated bars

Fundamental Concepts and Data Representation in Statistics

Guida di studio - Domande di pratica

Study guide - Flashcard