computed the sample mean to be 100.

A) A statisticspractitioner took a random sampleof 50 observations from a population whose standard deviationis 25 and computed the sample meanto be 100. Estimate the population mean with 90% confidence.

b) Repeat part a using a 95% confidence level

c) Repeat part a using a 99% confidence level

d) Describe the effect on the confidence intervalestimate of increasing the confidence level.

Please see attached file.

Confidence interval – mean

90% confidence level
100 mean
25 std. dev.
50 n
1.677 t (df = 49)
5.928 half-width
105.928 upper …

This solution calculates the population mean with 90%, 95% and 99% confidence level and explains the effect of increasing the confidence level percentage.