Q: Which formula is used to calculate the sample variance $s^2$?

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

Q: Which of the following is a key assumption for using the standard normal distribution in hypothesis testing?

The population is normally distributed or the sample size is large.

Q: Which of the following best describes the purpose of an OGIVE graph?

To display the cumulative frequency distribution of a dataset.

Q: A business analyst uses SPSS to analyze survey data. Which of the following is NOT a valid use of SPSS in this context?

Calculating the cost of goods sold

Q: Which of the following is a characteristic of a binomial experiment?

Each trial has only two possible outcomes.

Question 1

Which of the following best describes the main purpose of inferential statistics in business decision-making?

Accepted Answer

To estimate population parameters and test hypotheses using sample data.

Question 2

A manager wants to compare the average sales between two independent stores. Which statistical test should be used if the population variances are unknown but assumed equal?

Accepted Answer

Pooled variance t-test

Question 3

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

Accepted Answer

Standard deviation

Question 4

A company wants to estimate the proportion of customers satisfied with their service. Which formula should be used to calculate a 95% confidence interval for the population proportion $p$?

Accepted Answer

$ \hat{p} \pm z_{\alpha/2} \sqrt{\frac{\hat{p}(1-\hat{p})}{n}} $

Question 5

Which of the following statements about the Central Limit Theorem is correct?

Accepted Answer

It states that the sampling distribution of the sample mean approaches normality as sample size increases.

Question 6

A business analyst uses a histogram to display sales data. What type of variable is most appropriate for this graphical summary?

Accepted Answer

Interval or ratio

Question 7

If a hypothesis test results in a Type I error, what has occurred?

Accepted Answer

A true null hypothesis was incorrectly rejected.

Question 8

Which probability distribution is most appropriate for modeling the number of customer arrivals at a bank per hour?

Accepted Answer

Poisson distribution

Question 9

A company wants to test if the mean delivery time is less than 2 days. Which is the correct null and alternative hypothesis?

Accepted Answer

$ H_0: \mu \geq 2,\ H_1: \mu < 2 $

Question 10

Which formula is used to calculate the sample variance $s^2$?

Accepted Answer

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

Question 11

A business wants to forecast sales using advertising expenditure as a predictor. Which statistical method should be used?

Accepted Answer

Simple linear regression

Question 12

Which of the following is a key assumption for using the standard normal distribution in hypothesis testing?

Accepted Answer

The population is normally distributed or the sample size is large.

Question 13

A company collects data on the number of defective products in batches of 100. Which probability distribution should be used to model the number of defectives?

Accepted Answer

Binomial distribution

Question 14

Which of the following best describes the purpose of an OGIVE graph?

Accepted Answer

To display the cumulative frequency distribution of a dataset.

Question 15

A researcher wants to test if there is a difference in mean customer satisfaction scores between two related groups (before and after a new policy). Which test should be used?

Accepted Answer

Paired t-test

Question 16

Which formula is used to calculate the $z$-score for a value $x$ in a normal distribution with mean $\mu$ and standard deviation $\sigma$?

Accepted Answer

$ z = \frac{x - \mu}{\sigma} $

Question 17

A business analyst uses SPSS to analyze survey data. Which of the following is NOT a valid use of SPSS in this context?

Accepted Answer

Calculating the cost of goods sold

Question 18

Which of the following is a characteristic of a binomial experiment?

Accepted Answer

Each trial has only two possible outcomes.

Question 19

A company wants to compare the variances of two production processes. Which test should be used?

Accepted Answer

F-test

Question 20

Which formula is used to calculate the regression line in simple linear regression?

Accepted Answer

$ \hat{y} = b_0 + b_1 x $

QMS210: Applied Statistics for Business – Course Outline and Study Guide

Study Guide - Practice Questions

Study Guide - Flashcards