With individual lines at the checkouts, a store manager finds ...

[charchew]

With individual lines at the checkouts, a store manager finds that the standard deviation for the waiting times on Monday mornings is 5.2 minutes.
 
  After switching to a single waiting line, he finds that for a random sample of 29 customers, the waiting times have a standard deviation of 4.2 minutes. Use a 0.025 significance level to test the claim that with a single line, waiting times vary less than with individual lines.

Question 2

When a fair coin is flipped 10 times, the probability distribution of the number of tails, x, is as shown in the table. If Sue flips a coin 10 times and gets 9 tails, does that suggest that the coin is not fair?
 
  x P(x)
   0 0.001
   1 0.010
   2 0.044
   3 0.117
   4 0.205
   5 0.246
   6 0.205
   7 0.117
   8 0.044
   9 0.010
   10 0.001
 
  A) Yes B) No

[flexer1n1]

Answer to Question 1

Test statistic: X2 = 18.266. Critical value: X2 = 15.308. Fail to reject . There is not sufficient evidence to support the claim that with a single line waiting times have a smaller standard deviation.

Answer to Question 2

A

[charchew]

TY

[flexer1n1]

You're welcome