Question

A random sample of n = 64 observations has a mean x = 29.9 and a standard deviation s = 3.7.

Answer 1

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 = ±$1.669*\sqrt{\frac{3.7}{\sqrt{64} } } \\=0.7719$

b) Confidence interval 90%

= Mean±Marginof error

= $(29.128,30.672)$