Using the simple random sample of weights of women from a data set, we obtain th
ID: 3437711 • Letter: U
Question
Using the simple random sample of weights of women from a data set, we obtain these sample statistics n 40 andx 146.49 lb. Research from other sources suggests that the population of weights of women has a standard deviation given by o 32.97 lb. a. Find the best point estimate of the mean weight of all women. b. Find 90% confidence interval estimate of the mean weight of all women. Click here to view a t distribution table. Click here to view page 1 of the standard normal distribution table Click here to view age 2 of the standard normal distribution table a. The best point estimate is Type an integer or a decimal.) b. The 90% confidence interval estimate is Ib KH Ib. (Round to two decimal places as needed.)Explanation / Answer
a.
The best point estimate is the sample mean, xbar.
Thus,
best point estimate = xbar = 146.49 [ANSWER]
*******************
Note that
Lower Bound = X - z(alpha/2) * s / sqrt(n)
Upper Bound = X + z(alpha/2) * s / sqrt(n)
where
X = sample mean = 146.49
z(alpha/2) = critical z for the confidence interval = 1.644853627
s = sample standard deviation = 32.97
n = sample size = 40
Thus,
Lower bound = 137.9153538
Upper bound = 155.0646462
Thus, the confidence interval is
(137.92 , 155.06) [ANSWER]
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.