Answer:
(29.128,30.672)
Step-by-step explanation:
Given that a random sample of n = 64 observations has a mean x = 29.9 and a standard deviation s = 3.7.
a) the point estimate of the population mean μ.
= Sample mean = 29.9
For 90% we use t critical value since population standard deviation is not known.
T critical for 90% is 1.669
Margin of error = ±[tex]1.669*\sqrt{\frac{3.7}{\sqrt{64} } } \\=0.7719[/tex]
b) Confidence interval 90%
= Mean±Marginof error
= [tex](29.128,30.672)[/tex]
