In: Statistics and Probability
The company you are working for just received an order for 10
castings, made from precious
metals. The way the facility works is as follows: you first
schedule n castings for production
and order the first materials necessary. Then, each of the n
scheduled castings can turn out to
be of high quality with a probability of 0.90. All castings are
produced independently. You can
only sell castings of high quality to the customer. Answer the
following questions.
(a) Assume your company plans to produce n = 15 castings. What is
the probability they get
at least 10 castings of high quality to sell to the customer?
(b) Now, assume your company plans to produce n = 10 castings. What
is the probability they
get at least 10 castings (that is, exactly 10 castings out of the
scheduled 10) of high quality to
sell to the customer?
(c) Based on your answers in (b) and (c), would you recommend they
plan for 10 or 15 castings?
Summarize your reasoning in one sentence.
(d) Perform the same calculations for scheduling n = 11, 12, 13,
14. How many castings would
you opt to schedule? Show your results for each case of n and
summarize your reasoning in a
sentence.