Suppose a 95 confidence interval for the difference between the ...

[crobinson2013]

  Suppose a 95 confidence interval for the difference between the average age of females employed by Company A and the average age of females employed by Company B is (-4.7,6.5). Which of the following hypotheses can be tested at the level using the information given?
 

  a.H₀: versus H_a:
  b.H₀: versus H_a:
  c.H₀: versus H_a:
  d.H₀: versus H_a:

Question 2

 

If two independent random samples gave the following information, what are the estimated mean and standard error for the difference between the two means under the assumption of equal variances?
  Sample A: n_A = 10, , s_A = 15
  Sample B: n_B = 20, , s_B = 10

 

  a.The mean is 200 and the standard error is 12.5.
  b.The mean is 40 and the standard error is 11.84.
  c.The mean is 200 and the standard error is 4.59.
  d.The mean is 40 and the standard error is 4.59.

[nmyers]

Answer to Question 1

correct: c

Answer to Question 2

correct: d