1Construct a 95 confidence interval for the mean using the s
Solution
Getting the mean and standard deviation.
X = 10.91
s = 4.736489558
Note that
Lower Bound = X - t(alpha/2) * s / sqrt(n)
Upper Bound = X + t(alpha/2) * s / sqrt(n)
where
alpha/2 = (1 - confidence level)/2 = 0.025
X = sample mean = 10.91
t(alpha/2) = critical t for the confidence interval = 2.262157163
s = sample standard deviation = 4.736489558
n = sample size = 10
df = n - 1 = 9
Thus,
Lower bound = 7.521719485
Upper bound = 14.29828052
Thus, the confidence interval is
( 7.521719485 , 14.29828052 ) [ANSWER]
