Author Question: The manager of an online shop wants to determine whether the mean length of calling time of its ... (Read 116 times)

fox

  • Hero Member
  • *****
  • Posts: 540
The manager of an online shop wants to determine whether the mean length of calling time of its customers is significantly more than 3 minutes. A random sample of 100 customers was taken. The average length of calling time in the sample was 3.
 
  1 minutes with a standard deviation of 0.5 minutes. At a 0.05 level of significance, it can be concluded that the mean of the population is:A) significantly greater than 3.
  B) not significantly greater than 3.
  C) significantly less than 3.
  D) not significantly different from 3.10.

Question 2

A car company is interested in testing to see whether the mean miles that a car engine will last without changing oil is the same or different depending on which brand of oil is used.
 
  The engineers also wish to control for the type of transmission (manual or automatic) that is used. To conduct this test, the car company obtains enough engines so that all four oil brands can be tested in a design that involves no replication. Based on this information, how many engines will be needed to conduct the test?A) 4
  B) 8
  C) One for each oil type
  D) One for each factor in the study



josephsuarez

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

A

Answer to Question 2

B



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Glaucoma is a leading cause of blindness. As of yet, there is no cure. Everyone is at risk, and there may be no warning signs. It is six to eight times more common in African Americans than in whites. The best and most effective way to detect glaucoma is to receive a dilated eye examination.

Did you know?

Stevens-Johnson syndrome and Toxic Epidermal Necrolysis syndrome are life-threatening reactions that can result in death. Complications include permanent blindness, dry-eye syndrome, lung damage, photophobia, asthma, chronic obstructive pulmonary disease, permanent loss of nail beds, scarring of mucous membranes, arthritis, and chronic fatigue syndrome. Many patients' pores scar shut, causing them to retain heat.

Did you know?

Asthma cases in Americans are about 75% higher today than they were in 1980.

Did you know?

Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.

Did you know?

Chronic marijuana use can damage the white blood cells and reduce the immune system's ability to respond to disease by as much as 40%. Without a strong immune system, the body is vulnerable to all kinds of degenerative and infectious diseases.

For a complete list of videos, visit our video library