Question

Bill works for an insurance company and he wants to estimate the average time that a patient seeks emergency services. a random sample of 33 patients had an average weight time of 222 minutes with a sample standard deviation of 676 minutes. determine the confidence interval to estimate the average wait time using both 90% and 99% level of confidence.

a) what is the standard error of the sampling distribution?

b) what is the 90% confidence interval?

c) what is a 99% confidence interval?

Answer 1

Mean = 222

Sample size (n) = 33

Standard deviation (s) = 676

a)

b)

Confidence interval(in %) = 90

z @ 90.0% = 1.645

Since we know that

Required confidence interval = (222.0-193.5778, 222.0+193.5778)

Required confidence interval = (28.4222, 415.5778)

c)

Confidence interval(in %) = 99

z @ 99.0% = 2.576

Since we know that

Required confidence interval = (222.0-303.1347, 222.0+303.1347)

Required confidence interval = (-81.1347, 525.1347)