Author Question: An economist is interested in studying the incomes of consumers in a particular country. The ... (Read 96 times)

nmorano1

  • Hero Member
  • *****
  • Posts: 598
An economist is interested in studying the incomes of consumers in a particular country. The population standard deviation is known to be 1,000. A random sample of 50 individuals resulted in a mean income of 15,000. What total sample size would the economist need to use for a 95 confidence interval if the width of the interval should not be more than 100?
 
  A) n = 40 B) n = 1537 C) n = 385 D) n = 20

Question 2

The head librarian at the Library of Congress has asked her assistant for an interval estimate of the mean number of books checked out each day. The assistant provides the following interval estimate: from 740 to 920 books per day. If the head librarian knows that the population standard deviation is 150 books checked out per day, and she asked her assistant to use 25 days of data to construct the interval estimate, what confidence level can she attach to the interval estimate?
 
  A) 99.7 B) 99.0 C) 95.4 D) 98.0



tandmlomax84

  • Sr. Member
  • ****
  • Posts: 323
Answer to Question 1

B

Answer to Question 2

A



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question


 

Did you know?

The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.

Did you know?

Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.

Did you know?

Amoebae are the simplest type of protozoans, and are characterized by a feeding and dividing trophozoite stage that moves by temporary extensions called pseudopodia or false feet.

Did you know?

Many medications that are used to treat infertility are injected subcutaneously. This is easy to do using the anterior abdomen as the site of injection but avoiding the area directly around the belly button.

Did you know?

Studies show that systolic blood pressure can be significantly lowered by taking statins. In fact, the higher the patient's baseline blood pressure, the greater the effect of statins on his or her blood pressure.

For a complete list of videos, visit our video library