Question

In: Statistics and Probability

13. A manager wants to know whether customers in Taiwan, on average, would spend more than...

13. A manager wants to know whether customers in Taiwan, on average, would spend more than $2,000 per month on the service that is similar to what her company provides. The following information regarding the consumer behavior of 49 customers was provided by the marketing research team: sample mean = $2,400 and sample standard deviation = $1,800. Using the sample information provided and 0.05 significance level, determine the critical value and calculate the value of the test statistic.

A. Critical value = –1.96 & +1.96, and Test statistic = –1.56

B. Critical value = –1.645, and Test statistic = –1.56

C. Critical value = +1.645, and Test statistic = +1.56

D. Critical value = +1.96, and Test statistic = +1.56

14. Which of the following is NOT a characteristic of a normal variable?

A. It can be converted into the standard normal variable.

B. The values are from –∞ to +∞.

C. The center line is always at 0.

D. The probability of each individual value is virtually 0.

15. A tire manufacturer claims that his tires have a mean life of 60,000 miles when used under normal diving conditions. A firm that requires a larger number of these tires wants to test the claim. If the claim is correct, the firm will purchase the manufacturer’s tires; otherwise, the firm will seek another supplier. Now a random sample of 100 tires is taken and the mean and standard deviation of the 100 tires are found. Using these sample results, a 95% confidence interval for the mean life of the tire is estimated as from 56,789 to 63,211 miles. The manufacturer’s claim is tested at the 5% significance level. Based on the given information, what should the firm do?

A. The firm will seek another supplier.

B. Cannot be determined because of insufficient information.

C. The firm will purchase the manufacturer’s tires.

D. The firm will purchase half from the manufacturer and the other half from another supplier.

16. Because of the relatively high interest rates, most consumers attempt to pay off their credit card bills promptly. However, this is not always possible. An analysis of the amount of interest paid monthly by a bank’s Visa cardholders reveals that the amount is normally distributed with a mean of $1,735 and a standard deviation of $285. What interest payment is exceeded by only 15% of the bank’s Visa cardholders?

A. $1,438.60

B. $1,585.375

C. $1,884.625

D. $2,031.40

Expert Solution

orchestra answered 1 year ago

a) A researcher wants to test if boys spend more time playing sports on average than...

a) A researcher wants to test if boys spend more time playing sports on average than girls. Data is collected, resulting in the table below. It is known that the times for sports have a normal distribution in general. Group n Average number of hours SD Boy 35 5.2 3.3 Girl 25 3.5 5 Compute the test statistic that is corresponding to the test in the question 9. Round your answer to two decimal digits. b) Let the significance level...

A Thai restaurant wants to know whether more people order pad thai on working days than...

A Thai restaurant wants to know whether more people order pad thai on working days than on non-working days. A sample of 58 working days showed that the average number of orders of pad thai was 350, with an SD of 22. A sample of 62 non-working days showed the average number of orders of pad thai was 355 with an SD of 29. Is the average number of orders of pad thai on the non-working days larger than on...

A fund manager wants to know if it is equally likely that the Nasdaq Average will...

A fund manager wants to know if it is equally likely that the Nasdaq Average will go up each day of the week. For each day of the week, the fund manager observes the following number of days when the Nasdaq Average goes up. Day of the Week Observed Monday 192 Tuesday 189 Wednesday 202 Thursday 199 Friday 218 For the goodness-of-fit test, the null and alternative hypotheses are ________. H0: p1 = p2 = p3 = p4 = 1/4,...

A movie theater manager believes the average amount of money customers spend on snacks is over...

A movie theater manager believes the average amount of money customers spend on snacks is over $15. To test the claim, a theater employee tracks the spending of 25 randomly selected customers. The sample mean is $17.08 with a sample standard deviation of $4.81. a) What is the Null Hypothesis and the Alternative Hypothesis for the manager’s claim? b) Assuming the population is normal, should we use the Normal z-test or the Student’s t-test?

Best Western Gift shop is interested to know how much money, on average, their customers spend...

Best Western Gift shop is interested to know how much money, on average, their customers spend each visit in the housewares department. They go back through their records and draw a sample of 1,000 and calculate each customer’s average spending on housewares. a) Identify the population, sample, parameter, statistic, variable and data for this example. b) Describe a situation in which you would calculate a parameter rather than a statistic. Best Western determined that each customer’s spending is normally distributed...

6.20. A convenience store owner wants to know how long his customers spend browsing the store...

6.20. A convenience store owner wants to know how long his customers spend browsing the store before making a purchase. It is found that time spent is normally distributed with an average of m = 5 minutes and a standard deviation of s=2 : 2 minutes. Using a random sample of 14 customers, what is the probability that a customer, on average, will spend less than 4 minutes browsing the store?

A regional bank manager wants to know the difference between the mean amounts of time customers...

A regional bank manager wants to know the difference between the mean amounts of time customers wait in line at the drive-up window for three banks in his region. He randomly sampled seven wait times from each location. The data are given in the tables below. Bank 1 Bank 2 Bank 3 1 1.81 3.34 2.32 2 1.43 1.77 1.23 3 1.92 2.80 1.89 4 2.45 1.72 2.31 5 1.99 1.84 3.00 6 1.80 2.38 1.93 7 1.32 1.96 2.45...

PLEASE ANSWER ALL 4 QUESTIONS The owner of a bar wants to know whether their customers...

PLEASE ANSWER ALL 4 QUESTIONS The owner of a bar wants to know whether their customers prefer Johnnie Walker Whiskey or Seagram's Whiskey. The bar owner is undecided over which of two possible experiments she should use. In Experiment 1, each customer rates only one of the two drinks. In Experiment 2, each customer evaluates both types of whiskey. Experiment 1 Flip a coin for each customer to choose which type of drink (s)he will taste. Then each person rates...

If we as individuals would continue to spend more than we made, we would sooner or...

If we as individuals would continue to spend more than we made, we would sooner or later have to pay up or go bankrupt. Our government is in the same position or will be unless we get serious about our liabilities and reduce expenditures enough to reduce the deficits or increase revenues enough to pay our bills and have some left over to pay the old bills. Evaluate this statement

1. A firm would like to know the average time its workers spend on a certain...

1. A firm would like to know the average time its workers spend on a certain task. The firm takes a sample of 35 workers and finds that they take, on average, 13 minutes to complete the task, with a sample standard deviation of 3 minutes. Construct a 95% confidence interval for the population mean. a) State the critical value: b) Calculate the margin of error (round to the thousandths place): c) State the lower and upper values of the...