Answer:
The confidence interval is 27.5 hg less than mu less than 29.1 hg
(A) Yes, because the confidence interval limits are not similar.
Step-by-step explanation:
Confidence interval is given as mean +/- margin of error (E)
mean = 28.3 hg
sd = 6.1 hg
n = 202
degree of freedom = n-1 = 202-1 = 201
confidence level (C) = 95% = 0.95
significance level = 1 - C = 1 - 0.95 = 0.05 = 5%
critical value corresponding to 201 degrees of freedom and 5% significance level is 1.97196
E = t×sd/√n = 1.97196×6.1/√202 = 0.8 hg
Lower limit = mean - E = 28.3 0.8 = 27.5 hg
Upper limit = mean + E = 28.3 + 0.8 = 29.1 hg
95% confidence interval is (27.5, 29.1)
When mean is 28.3, sd = 6.1 and n = 202, the confidence limits are 27.5 and 29.1 which is different from 27.8 and 29.6 which are the confidence limits when mean is 28.7, sd = 1.8 and n = 17