BUS 204 Week 5 Assignment

BUS 204 Week 5 Assignment  | MiraCosta College

Question 1

A grocery store manager is preparing a presentation with bar charts and line charts to justify hiring more staff. She is using which general type of statistical analysis?

Descriptive statistics  

Random sampling 

Inferential statistics 

Quantitative statistics

Question 2

When an accounting auditor randomly selects 80 invoices from ALL supplier accounts to check for errors, he has selected:

a convenience sample.  

a census.  

a personal observation. 

a sample from the population.

Question 3

The Gallup polling company has divided the population into subgroups based on income class (lower, middle, and upper). The company then collects a random sample from each subgroup. This ensures that data from each subgroup is included in the sample. What kind of statistical sampling is this?

Stratified random sampling 

Convenience sampling  

Cluster sampling  

Simple random sampling

Question 4

An automaker wants to advertise the claim that their new electric vehicle is capable of over 300 miles of range, so it tests a subset of vehicles. Based on this test, the automaker was able to conclude that the vehicle can drive at least 300 miles on a single charge. This is an example of:

numerical measures.  

quantitative models.  

descriptive statistics.  

inferential statistics.

Question 5

The human resources department at Qualcomm conducted an employee satisfaction survey at the beginning of 2020. Data collected at this fixed point in time are:

   Time-series data  

Cross-sectional data 

Quantitative data  

Nominal data

Question 6

Qualcomm recently conducted an employee satisfaction survey. Data collected included variables such as age, gender, current salary, level of overall satisfaction, number of years with the company, and job title. Match the following variables to their data measurement level.

Current Salary            

Level of Overall Satisfaction             

Job Title            

Question 7

The daily stock closing prices for Home Depot would be classified as which of the following?

Nominal data 

Cross-sectional data 

Time-series data 

Ordinal data

Question 8

MiraCosta College analyzed the GPA's of students along with the number of hours they sleep. An appropriate graph for analyzing the relationship between these two variables is:

a histogram. 

a line chart. 

a pie chart. 

a scatter diagram.

Question 9

Petco wants to display the the types of pets their customers own to show the diverse pet preferences of their entire customer base. If you were making the presentation, what graph is best?

Histogram 

Ogive 

Scatter diagram 

Pie chart

Question 10

A financial advisor wants to show clients how their retirement portfolio has changed over the last 12 months. The best type of chart to use is:    

a line chart

a histogram 

a pie chart 

a bar chart

Question 11

Geico Insurance wants to understand what kind of relationship exists between rainfall (in inches) and the number of car accidents. Plot a scatter diagram with the data below and indicate what kind of relationship (if any) exist between x and y.

Rainfall (x)           Number of Car Accidents (y)

2.75        19

0.5          5

4              25

1              12

5              28

There is a negative linear relationship between the two variables.  

There is a positive linear relationship between the two variables.  

There is no apparent relationship between the two variables.  

There is a perfect linear relationship between the two variables.

Question 12

Assuming you have data for a variable with 3,600 values, using the 2k ≥ n guideline, what is the least number of groups, or classes that should be used to develop a grouped data frequency distribution?

13  

12 

11  

10

Question 13

Which of the following is NOT TRUE when developing a frequency distribution with classes?

Classes should be of equal width.  

There should be between 2 and 10 classes. 

Classes must be mutually exclusive.  

Classes should not be empty.

Question 14

The data set below shows the number of flights taken by 20 employees for business travel at a small consulting firm in 2019

9              22           35           44           18

23           41           11           15           25

26           22           3              16           35

12           30           28           29           21

Develop a frequency distribution for the above data. (Let the width of your classes be 10 units and start your first class as 0 - 9.) Enter into the table below.

Develop a relative frequency distribution for the data. Enter into the table below. Do not round.

Class      Number of Flights Taken              Frequency          Relative

Frequency

1              0 - 9       

2

3

4

5             

Question 15

If you were a manager at the small consulting firm:

•             What would you observe from the table and the histogram in the question above? (e.g. most frequent class)

•             Give an example of a business decision you could make with this knowledge.

[While you are not required to submit a histogram for the exam, it is recommended you develop one using Excel or by hand to answer this question].

Normally the most frequent number of flights group is 20 to 29. It looks like a bell shaped distribution. I feel that number of business trips is more for a small company. So, I will try to reduce it.

The most frequent class of flights is class 3 at 20-29 flights. Followed by class 2 at 10-19 flights.

Knowing the typical number of flights can help a manager:

•             Negotiate deals with airlines (discounts, frequent flier miles, free flights)

•             Estimate travel budgets

•             Understand employees' availability of being in the office

•             Help with work life balance of employees

Question 16

The symbol μ is used to represent the:

standard deviation 

variance 

population mean 

sample mean

Question 17

Which of the following is the MOST frequently used measure of variation?

The standard deviation 

The variance

The range  

The mode

Question 18

If a restaurant manager selected a sample of customers and computed the average time spent dining in the restaurant for this sample of customers, he has computed:

a statistic.  

a parameter.  

an ordinal value.  

a nominal value.

Question 19

The Empirical Rule states that for a bell-shaped distribution, approximately 68% of data should lie:

within two standard deviations from either side of the mean.  

within three standard deviations from either side of the mean.  

within one standard deviation from either side of the mean.  

within four standard deviations from either side of the mean.

Question 20

If a data set has 199 sorted values, what value corresponds to the 3rd quartile? Hint: find the location index, i.

The 165th value  

The  200th value  

The 150th value  

The 75th value

Question 21

A small landscaping company has 7 employees. The numbers of years these employees have worked for the company are shown below. The mode number of years is:

2              11           7              10           13           8              7

2 years. 

7 years. 

11 years. 

10 years.

Question 22

A small landscaping company has 7 employees. What is the median number of years that these employees have worked for this company?

2              11           7              10           13           8              7

10 years.

13 years.

8 years.

7 years.

PartialQuestion 23

Uber rides average $25.00 per ride with a standard deviation of $7.00. Lyft rides average $20 per ride with a standard deviation of $8.00.

Make sure to enter your coefficient of variation as a PERCENTAGE (no decimals).

What is the coefficient of variation for Uber rides? 

What is the coefficient of variation Lyft rides? 

Which ridesharing service shows a MORE dispersed distribution? 

Question 24

An investment portfolio is made up of shares from 5 different companies (data provided in the table below).

                Stock Price          Number of Shares

Company A         $50         1,250

Company B         $65         1,000

Company C         $100       500

Company D         $85         1,300

Company E         $150       250

Compute the weighted average (mean) for the stock price for this investment portfolio. Round your answer to the hundredths place (2 decimals). Note the system may add 0's, but that won't affect your answer. 

Question 25

EXTRA CREDIT QUESTION (Up to 5 points possible) - Explain why the weighted mean is a better choice over the mean in the investment portfolio example above?

As number of stocks at different prices are of different frequency (weight). So, weighted mean is netter here to calculate mean.

The weighted mean takes into account the number of shares owned (the weight).

Its a more reasonable measure of the average stock price, rather than treating all companies as equals.

Question 26

A car dealership tracks the number of cars sold in the last six months of 2019. Assume the data represent a sample. (20 pts)

Month  Cars sold (x)

July        5

August  8

September         10

October               6

November          10

December           6

NOTE: Round all answers to the hundredths place (2 decimal places)

a. Compute the sample mean. 

b. Compute the sample variance. 

c. Compute the sample standard deviation. 

d. Compute the z-score for the month of November. 

e. If the above data were a population, the denominator used to find the population variance, would be (enter the numeric value): 

Question 27

Of the last 100 customers entering Starbucks, 20 buy a croissant. If the classical probability assessment applies, the probability that the next customer will buy a croissant is:  

1.00  

0.80  

0.50  

0.20

Question 28

Economist A believes the U.S. economy has an 80% chance of recovering quickly from the recession whereas Economist B believes the U.S. economy has a 45% chance of recovering quickly. What method of probability assessment is MOST LIKELY being used in this situation?

Classical probability based on the ratio of the number of ways the event can occur  

Independent probability based on two unrelated outcomes  

Subjective probability based on expert opinion 

Relative frequency based on previous history

Question 29

When the San Diego Padres play a game, there are 3 possible outcomes that can occur: they can win, lose, or tie. The events are:  

mutually exclusive.  

all inclusive.  

dependent events.

independent.

Question 30

SD Bicycles makes two mountain bike models in 3 colors. Below are the production volumes:

What is the joint probability that a product manufactured is a XB-50 and white?

0.1324 

0.2088  

0.3075 

0.2037

Question 31

McDonald's has determined that the chance a customer orders a soda is 0.80. The probability that a customer orders chicken nuggets is 0.50 and the probability that a customer orders french fries is 0.70. If a customer places an order, what is the probability that the order will include a chicken nuggets and no fries if these two events are independent?

0.50 

0.15 

0.56 

0.35

Question 32

A medical doctor initially assigned an 80% chance that a patient has a particular disease. However, after seeing positive results from a lab test, he changed his assessment to 95%. A useful tool for the doctor to revise his prior probability assessment with the lab test results is:

Subjective Assessment  

Addition Rules  

Bayes' Theorem

Multiplication Rules

PartialQuestion 33

Vons Grocery store gets its organic fruit from local farms. The manager has found a case of rotten fruit. Use Bayes’ Theorem to identify which farm is most likely to be responsible for the bad fruit and provide this to the manager.

Which farm is most likely responsible? 

Question 34

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I pledge on my honor that I have not given or received any unauthorized assistance on this exam.