Question details

ECO 250 Final Exam
$ 19.99

ECO 250 Final

Be sure to round answers to at least two decimals! You will not get credit for the answer 3.1 if the actual answer is 3.1157, but you would get credit for 3.12, 3.116, or 3.1157.

 

Question 1 

The mathematical science that deals with the collection, analysis, and presentation of data is 

 

Economics 

 

Mathematical analysis 

 

Statistics 

 

Data analysis 

 

Question 2 

Sampling error is the difference between the __________ and the parameter. 

 

Sample 

 

Sample mode 

 

Statistic 

 

None of the above 

 

 

Question 3 

The __________ is the probability distribution used in place of the normal distribution to calculate a confidence interval when the population standard deviation is unknown. 

 

Uniform distribution 

 

Binomial distribution 

 

Exponential distribution 

 

Student's t-distribution 

 

 

Question 4 

A __________ is a distribution in which the probability of any interval occurring is equal to any other interval with the same width. 

 

Normal distribution 

 

Uniform distribution 

 

Binomial distribution 

 

Student's t-distribution 

 

 

Question 5 

The number of rushing touchdowns for the Minnesota Vikings in a season is an example of 

 

Nominal data 

 

Ratio data 

 

Interval data 

 

Ordinal data 

 

Question 6 

Which is a continuous random variable? 

 

The number of students in an ECO 250 class. 

 

The number of births in a hospital on a given day. 

 

The hourly earnings of a call center employee in Boston. 

 

The number of fives obtained in four rolls of a die. 

 

 

Question 7 

The empirical rule states if a distribution is symmetrical and bell-shaped, approximately 68%, 95%, and _______ of its data values will fall within one, two, and three standard deviations above and below the mean, respectively. 

 

99.5% 

 

98% 

 

99.7% 

 

99% 

 

 

Question 8 

__________ is the probability that the interval estimate will include the population parameter of interest, such as a mean. 

 

Significance level 

 

Confidence level 

 

Degrees of freedom 

 

Margin of error 

 

 



Question 9 

The __________ is a variable that represents the probability that any given confidence interval will not contain the true population mean. 

 

Significance level 

 

Degrees of freedom 

 

Confidence level 

 

Margin of error 

 

 

Question 10 

What is an error that occurs when the null hypothesis is rejected when, in reality, it is true? 

 

None of the above 

 

Type I error 

 

Sampling error 

 

Type II error 

 

Question 11 

Which is a time series variable? 

 

VISA balances of 30 students on December 31 of this year. 

 

Dollar exchange rates yesterday against 10 other world currencies 

 

Net earnings reported by Xena Corp for the last 10 quarters. 

 

Titles of the top 10 movies in total revenue last week 

 

 

Question 12 

A tire company performs quality-control tests on the monthly output of its best-selling model tire at each of its plants. Each month a random sample of 25 tires is selected from each plant and tested to see if the average tread life of that plant’s tires is above specifications. For one plant, the random sample of 25 tires had a sample mean of 39,500 miles and a sample standard deviation of 3,300 miles. The company performs a hypothesis test at the .05 level of significance to see if there is evidence that the average tread life is greater than 38,000. Based on this sample, the company should: 

 

Reject the null hypothesis and conclude there is evidence that the average tread life is greater than 38,000 miles. 

 

Fail to reject the null hypothesis and conclude there is not evidence that the average tread life is greater than 38,000 miles. 

 

Reject the null hypothesis and conclude there is not evidence that the average tread life is greater than 38,000 miles. 

 

Fail to reject the null hypothesis and conclude there is evidence that the average tread life is greater than 38,000 miles 

 

Question 13 

What is the probability of observing a sample mean at least as extreme as the one selected for the hypothesis test, assuming the null hypothesis is true? 

 

p-value 

 

Alpha 

 

Beta 

 

Confidence level 

 

 

Question 14 

Which is not a characteristic of a binomial experiment? 

 

The experiment consists of an infinite number of trials. 

 

Each trial has only two possible outcomes: a success or a failure 

 

Each trial is independent of the other trials in the experiment 

 

The probability of success is equal to one minus the probability of failure 

 

 

Question 15 

A __________ is a continuous distribution that is bell shaped and symmetrical around the mean. 

 

Exponential distribution 

 

Normal distribution 

 

Uniform distribution 

 

Binomial distribution 

 

 

Question 16 The critical z-score for an 85% confidence level is ________. 

 

 1.44 

 

 1.28 

 

 2.33 

 

 1.96 

 

 



Question 17 

YouTube would like to test the hypothesis that the average length of an online video watched by a user is more than 6 minutes. A random sample of 40 people watched online videos that averaged 6.6 minutes in length. The population standard deviation for the length of online videos is 1.7 minutes. YouTube would like to set  α=0.05. The p-value for this hypothesis test would be _________. 

 

0.0644 

 

0.0395 

 

0.0129 

 

0.0268 

 

Question 18 

A professor would like to test the hypothesis that the average number of minutes that a student needs to complete a statistics exam is equal to 45 minutes. The correct hypothesis statement would be 

 

 

 

 

 

 

 

 

 

 

 

 

Question 19 

What should you do when the p-value is less than the significance level? 

 

Fail to reject the null hypothesis 

 

Accept the alternative hypothesis 

 

Accept the null hypothesis 

 

Reject the null hypothesis 

 

 

Question 20 

Consider the following set of numbers: 10, 25, 13, 18, 40, 5. Determine the median and variance of these data. 

 

median = 18.5, variance = 12.57 

 

median = 15.5, variance = 157.9 

 

median = 15.5, variance = 35 

 

median = 18.5, variance = 473.83 

 

 

Question 21 

A point estimate, also called a statistic, is a single value that describes the population of interest, with the sample mean being the most common. 

 

True 

 

False 

 

 

Question 22 

The margin of error is the width of the confidence interval between the lower limit and the upper limit. 

 

True 

 

False 

 

 

Question 23 

The alternative hypothesis represents the status quo and involves stating the belief that the population parameter is   a specific value and is always associated with the equal sign. 

 

True 

 

False 

 

 

Question 24 

A z-score measures the number of standard deviations a value is from its mode. 

 

True 

 

False 

 

 

Question 25 

Suppose Nike's average stock price this year is $15.00 with a standard deviation of $3.00, and Under Armour's average stock price this year is $24.00 with a standard deviation of $4.00. According to this data, Nike's stock price is more consistent than Under Armour's stock price. 

 

True 

 

False 

 

 

Question 26 

The Central Limit Theorem states that sample means, drawn from a normally distributed population, will be normally distributed. 

 

True 

 

False 

 

 

Question 27 

A low p-value indicates a high probability that the null hypothesis is not true. 

 

True 

 

False 

 

Question 28 

If the absolute value of the test statistic is less than the critical value in a two-tailed hypothesis test, then the decision is to reject the null hypothesis. 

 

True 

 

False 

 

 

Question 29 

Consider the hypotheses

H0: Defendant is innocent

H1: Defendant is guilty

If a court acquits every defendant, they will never commit Type II error.

 

True 

 

False 

 

 

Question 30 

If we do not have evidence to support the alternative hypothesis, then we accept the null hypothesis. 

 

True 

 

False 

 



Question 31 

Suppose the average puppy weighs 10 pounds. A sample of 10 puppies yields a sample mean of 13.2 pounds and a sample standard deviation of 2.78 pounds. Assume the population standard deviation is known to be 5.25.You want to test whether the sample mean differs from the population mean of 10 pounds at a 5 percent level of significance using a two-tailed test. What are your null and alternative hypotheses? 

 

 

 

 

 

 

 

 

 

 

 

Question 32 

Suppose the average puppy weighs 10 pounds. A sample of 10 puppies yields a sample mean of 13.2 pounds and a sample standard deviation of 2.78 pounds. Assume the population standard deviation is known to be 5.25.You want to test whether the sample mean differs from the population mean of 10 pounds at a 5 percent level of significance using a two-tailed test. Calculate the test statistic for the sample data. 

 

 

 

Question 33 

Suppose the average puppy weighs 10 pounds. A sample of 10 puppies yields a sample mean of 13.2 pounds and a sample standard deviation of 2.78 pounds. Assume the population standard deviation is known to be 5.25.You want to test whether the sample mean differs from the population mean of 10 pounds at a 5 percent level of significance using a two-tailed test. State the critical value. 

 

 

 

Question 34 

Suppose the average puppy weighs 10 pounds. A sample of 10 puppies yields a sample mean of 13.2 pounds and a sample standard deviation of 2.78 pounds. Assume the population standard deviation is known to be 5.25.You want to test whether the sample mean differs from the population mean of 10 pounds at a 5 percent level of significance using a two-tailed test. Determine whether or not the null hypothesis should be rejected. 

 

Fail to reject the null hypothesis. 

 

Reject the null hypothesis. 

 



Question 35 

Consider the following data on the number of beers consumed by a sample of football fans during a game:

3       5       0       2       5       3.

 

Calculate the mean number of beers.

 

 

Question 36 

Consider the following data on the number of beers consumed by a sample of football fans during a game:

3       5       0       2       5       3.

 

Calculate the median.

 

 

 

Question 37 

Consider the following data on the number of beers consumed by a sample of football fans during a game:

3       5       0       2       5       3.

Calculate the mode (mark all that apply).

 



 



 



 



 

Question 38 

Consider the following data on the number of beers consumed by a sample of football fans during a game:

3       5       0       2       5       3.

Calculate the variance.

 

 

 

Question 39 

You check the weather forecast every morning. On average, it is rainy 20 percent of the time. Consider the next 5 days. What is the probability it will be rainy exactly 1 day? 

 

 

Question 40 

You check the weather forecast every morning. On average, it is rainy 20 percent of the time. Consider the next 5 days. What is the probability it will be rainy at most 2 days? 

 

 

 

Question 41 

The average batter life of the iPhone 4S is reported to be 6.0 hours by Apple. Assume that the population standard deviation for the better life for this cell phone is 30 minutes. A random sample of 50 iPhones had an average better life of 5.7 hours. Determine the margin of error (in hours) for the 90% confidence interval for this sample. 

 

 

Question 42 

The average batter life of the iPhone 4S is reported to be 6.0 hours by Apple. Assume that the population standard deviation for the better life for this cell phone is 30 minutes. A random sample of 50 iPhones had an average better life of 5.7 hours. Determine the lower confidence limit (LCL), in hours, for the 90% confidence interval for this sample. 

 

 



Question 43 

The average batter life of the iPhone 4S is reported to be 6.0 hours by Apple. Assume that the population standard deviation for the better life for this cell phone is 30 minutes. A random sample of 50 iPhones had an average better life of 5.7 hours. Determine the upper confidence limit (UCL), in hours, for the 90% confidence interval for this sample. 

 

 



 

Question 44 

Consider the following discrete probability distribution.

    X            P(X)    

0    0.2

1    0.3

2    0.4

3    0.1

Total    1.0

Calculate the mean of this distribution.

 

 

 

Question 45 

Consider the following discrete probability distribution.

    X            P(X)    

0    0.2

1    0.3

2    0.4

3    0.1

Total    1.0

Calculate the variance of this distribution.

 

 Question 46 

The commute time to work for a particular employee follows a continuous uniform distribution with a minimum time of 9 minutes and a maximum time of 25 minutes.

What is the mean of this distribution?

 

 

Question 47 

The commute time to work for a particular employee follows a continuous uniform distribution with a minimum time of 9 minutes and a maximum time of 25 minutes.

What is the probability that the employee's next commute to work will require less than 10 minutes?

 

 

Question 48 

The commute time to work for a particular employee follows a continuous uniform distribution with a minimum time of 9 minutes and a maximum time of 25 minutes.

What is the probability that the employee's next commute time will require between 12 minutes and 20 minutes?

 

 

Question 49 

Consider the following hypothesis:

 

 H1: μ>25

Given that   calculate the test statistic.

 

 



Question 50 

Consider the following hypothesis:

 

 H1: μ>25

Given that   state the critical value.

 

 

Question 51 

Consider the following hypothesis:

 

 H1: μ>25

Given that   determine whether or not the null hypothesis should be rejected.

 

Fail to reject the null hypothesis 

 

Reject the null hypothesis 

 

 



Question 52 

A tire manufacturer selected a random sample of 50 tires of a particular model chosen from the past month’s production and used destructive testing to determine the tread life of each tire. The sample mean was 42,300 miles and the sample standard deviation was 7,500 miles. What is the 95% confidence interval estimate for the tread life of that entire model produced in the past month? 

 

 

 

 

 

 

 

 

 

 

 

 

 

Question 53 

Suppose the average number of complaints received by Christiana Hospital from patients is 7.4 every four weeks. Assume the number of complaints per month follows the Poisson distribution.

What is the probability of exactly four complaints during the next four weeks?

 

 

Question 54 

Suppose the average number of complaints received by Christiana Hospital from patients is 7.4 every four weeks. Assume the number of complaints per month follows the Poisson distribution.

What is the probability of four or more complaints during the next four weeks?

 

 

 

Question 55 

Suppose the average number of complaints received by Christiana Hospital from patients is 7.4 every four weeks. Assume the number of complaints per month follows the Poisson distribution.

What is the probability of exactly three complaints during the next two weeks?

 

 

 

Question 56 

Zombies eat, on average, 5 brains per day. Assume the actual number of brains eaten per day follows the normal distribution with a standard deviation of 0.29 brains. What is the probability that a zombie will eat exactly 3.2 brains tomorrow? 

Available solutions
  • ECO 250 Final Exam
    $19.99

    ECO 250 Final Pin It Be sure to round answers to at least two decimals! You will not get credit for the answer 3.1 if the actual answer is 3.1157, but you would get credit for 3.12, 3.116, or 3.1157. Question 1 The mathematical science that deals with the collection, analysis, and presentation of data is Economics Mathematical analysis Statistics Data analysis Question 2 Sampling error is the difference between the __________ and the parameter. Sample Sample mode Statistic None of the above Question 3 The __________ is the probability distribution used in place of the normal distribution to calculate a confidence interval when the population standard deviation is unknown. Uniform di

    Submitted on: 07 Jul, 2017 11:19:52 This tutorial has not been purchased yet .