Questions from Business Statistics

Q: A market survey has shown that people will spend an average of

A market survey has shown that people will spend an average of $2.34 each for your product next year, based on a sample survey of 400 people. The standard deviation of the sample was $0.72. Find the t...

Q: Your quality control department has just analyzed the contents of 20 randomly

Your quality control department has just analyzed the contents of 20 randomly selected barrels of materials to be used in manufacturing plastic garden equipment. The results found an average of 41.93...

Q: Find the 95% confidence interval for the amounts that your regular

Find the 95% confidence interval for the amounts that your regular customers spent on your products last month, viewing the data from Table 4.3.1 of Chapter 4 as a random sample of customer orders. T...

Q: For the annual salary levels: a. Construct a histogram

For the annual salary levels: a. Construct a histogram and indicate the average and standard deviation. b. How many employees are within one standard deviation from the average? How does this compare...

Q: Find the 99% confidence interval for the strength of cotton yarn

Find the 99% confidence interval for the strength of cotton yarn used in a weaving factory based on the data in problem 23 of Chapter 4. Data from problem 23: Consider the strength of cotton yarn us...

Q: Find the 99.9% confidence interval for the weight of

Find the 99.9% confidence interval for the weight of candy bars before intervention, based on the data in Table 5.5.4 of Chapter 5. Table 5.5.4:

Q: Find the one-sided 95% confidence interval for the weight

Find the one-sided 95% confidence interval for the weight of candy bars after intervention, based on the data in Table 5.5.4, indicating that the population mean weight is no more than some amount. T...

Q: From a list of the 729 people who went on a cruise

From a list of the 729 people who went on a cruise, 130 were randomly selected for interview. Of these, 112 said that they were very happy with the accommodations. Find the 95% confidence interval for...

Q: The amount of caffeine (milligrams) in randomly sampled cups of

The amount of caffeine (milligrams) in randomly sampled cups of coffee was as follows: 112:8,86:4, 45:9,110: 3, 100:3,93:3, 101:9,115:7,92:5,117:3,105:6,81:6 a. Find the one-sided 99% confidence inter...

Q: Intensities have been measured for eight flashlights. Find the critical t

Intensities have been measured for eight flashlights. Find the critical t value to use for each of the following confidence interval calculations: a. Two-sided 95% confidence. b. Two-sided 99% confide...