Any help please The National Student Loan Survey collects da
Any help please.
Solution
Note that
Margin of Error E = z(alpha/2) * s / sqrt(n)
Lower Bound = X - z(alpha/2) * s / sqrt(n)
Upper Bound = X + z(alpha/2) * s / sqrt(n)
where
alpha/2 = (1 - confidence level)/2 = 0.025
X = sample mean = 18900
z(alpha/2) = critical z for the confidence interval = 1.959963985
s = sample standard deviation = 49000
n = sample size = 1280
Thus,
Margin of Error E = 2684.350281
Lower bound = 16215.64972
Upper bound = 21584.35028
Thus, the confidence interval is
( 16215.64972 , 21584.35028 ) [ANSWER]
