SOLUTION: PROBLEM 3
Mall security estimates that the average daily per-store theft is exactly $250, but wants to determine the accuracy of this statistic. The company researcher takes a sa
Algebra ->
Probability-and-statistics
-> SOLUTION: PROBLEM 3
Mall security estimates that the average daily per-store theft is exactly $250, but wants to determine the accuracy of this statistic. The company researcher takes a sa
Log On
Question 366430: PROBLEM 3
Mall security estimates that the average daily per-store theft is exactly $250, but wants to determine the accuracy of this statistic. The company researcher takes a sample of 81 clerks and finds
X(BAR) = $210
S = $40.
a) Test at α = .001
b) Construct a 90% CIE of μ
I Tried this for Part a
Z = and I got 9. From there I get confused and don't know what to do next or even if my first answer for part a is right.
Any help would be greatly appreciated. If you can explain how you got the answer that would be even better.
You can put this solution on YOUR website! Mall security estimates that the average daily per-store theft is exactly $250, but wants to determine the accuracy of this statistic. The company researcher takes a sample of 81 clerks and finds
X(BAR) = $210
S = $40.
a) Test at alpha = .001
b) Construct a 90% CIE of u
Feedback:
Part a::::
Ho: u = 250
Ha: u is not equal to 250
-----
I use a t-statistic for mean problems involving sample size.
-----
The critical values are +/-3.416337
The test statistic is t(210) = (210-250)/(40/ sqrt(81)) = -9
-----
Conclusion: Since the ts is in the rejection interval,
reject Ho.
===========================
Part b:::
Construct a 90% CIE of u
---
x=bar = 210
E = 1.6641 = 7.3961
---
90% CIE: 210-7.3961 < u < 210+7.3961
90% CIE: 202.6039 < u < 217.3961
=======================================
Let me know if this helps.
=======================================
Cheers,
Stan H.
----
(