Question

Suppose just over 2500 cell phones are produced at a factory today. Management would like to ensure that the phones' display screens meet their quality standards before shipping them to retail stores. Since it takes about 10 minutes to inspect an individual phone's display screen, managers decide to inspect a sample of 50 phones from the day's production. (a) Explain why it would be difficult for managers to inspect an SRS of 50 phones produced today. (b) An eager employee suggests that it would be easy to inspect the last 50 phones that were produced today. Obviously, this employee never took a stats class! Explain why this is not a good method. (c) Another employee that did take a stats class recommends inspecting every 50th phone produced today. What sampling method are they using?

          Suppose just over 2500 cell phones are produced at a factory
today.  Management would like to ensure that the phones'
display screens meet their quality standards before shipping them
to retail stores.  Since it takes about 10 minutes to inspect
an individual phone's display screen, managers decide to inspect a
sample of 50 phones from the day's production.
(a) Explain why it would be difficult for managers to inspect an
SRS of 50 phones produced today.
(b) An eager employee suggests that it would be easy to inspect
the last 50 phones that were produced today.  Obviously, this
employee never took a stats class!  Explain why this is not a
good method.
(c)  Another employee that did take a stats class
recommends inspecting every 50th phone produced today.  What
sampling method are they using?

Added by Shawn C.

Question

Please give Ace some feedback