Author Question: The manager of an online shop wants to determine whether the mean length of calling time of its ... (Read 100 times)

fox

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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

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Answer to Question 1

A

Answer to Question 2

B



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