Questions from Statistics Principles

Q: A food service manager wants to be 95% certain that the

A food service manager wants to be 95% certain that the error in the estimate of the mean number of sandwiches dispensed over the lunch hour is l O or less. What sample size should be selected if a pr...

Q: Refer to Exercise 5.33, but suppose that the projects

Refer to Exercise 5.33, but suppose that the projects are scheduled consecutively with A in the first year and B in the second year. Th e company's chance of winning project A is still . 50. Instead o...

Q: A zoologist wishes to estimate the mean blood sugar level of a

A zoologist wishes to estimate the mean blood sugar level of a species of animal when injected with a specified dosage of adrenaline. A sample of 55 animals of a common breed are injected with adrenal...

Q: Refer to the data on the number of extracurricular activities in which

Refer to the data on the number of extracurricular activities in which 30 students participated in the past week. These data have n = 30, x = 1.925, s = 1.607 activities (a) Obtain a 98% confidence...

Q: After feeding a special diet to 80 mice, the scientist measures

After feeding a special diet to 80 mice, the scientist measures their weight in grams and obtains x = 35 grams and s = 4 grams. He states that a 90% confidence interval for µ is given by...

Q: The daily number of kayaks sold, X, at a water

The daily number of kayaks sold, X, at a water sports store has the probability distribution (a) Find the expected number of kayaks sold in a day. (b) Find the standard deviation of the number of kay...

Q: In a recent year, 67% of persons 22-33

In a recent year, 67% of persons 22-33 years old held passports. From a random sample of size n = 79 collected today, 61 are passport holders. (a) Estimate the proportion of persons 22-33 years old w...

Q: With reference to Exercise 8.88, (a)

With reference to Exercise 8.88, (a) Conduct a test of size .OS with the intent of establishing that the proportion today is larger than .67. (b) Find a 95% confidence interval for that proportion....

Q: Out of a sample of n = 625 students interviewed, 139

Out of a sample of n = 625 students interviewed, 139 had missed at least one class last week. Obtain a 95% confidence interval for p = proportion of all students that missed at least one class last we...

Q: With reference to Exercise 8.90, conduct a test with

With reference to Exercise 8.90, conduct a test with the intent of establishing that p > .20. (a) Formulate the null and alternative hypotheses. (b) Determine the test statistic. (c) Give the form...