7.9 A company is having a new corporate website developed. In the final testing phase the...

7.9 A company is having a new corporate website developed. In the
final testing phase the download time to open the new home
page is recorded for a large number of computers in office and
home settings. The mean download time for the site is
3.61 seconds. Suppose that the download times for the site are
normally distributed with a standard deviation of 0.5 seconds. If
you select a random sample of 30 download times:
a. What is the probability that the sample mean download time
is less than 3.75 seconds?
b. What is the probability that the sample mean is between
3.70 and 3.90 seconds?
c. The probability is 80% that the sample mean is between
which two values symmetrically distributed around the
population mean?
d. The probability is 90% that the sample mean is less than
what value?

Expert Solution

(a)

(b)

(c)

(d)

orchestra answered 2 years ago

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