Discussion:
Q1: A 90 % confidence interval for a situation is developed and is given by the following 48 < µ < 64.
a) Give the value of the sample mean that was used in developing this interval.
b) Give the value of the margin of error that was used in developing this interval.
Q2: Calculate the appropriate critical z-value for each of the following confidence levels?
a) 95% confidence interval
b) 80% confidence interval
Q3: What happens to the size (width) of a confidence interval in a problem if:
a) the percent of desired confidence (confidence level) increases from 80% to 90%? Does it get wider or narrower?
b) the size of the sample used to produce the confidence interval is decreased?
c) the margin of error is decreased?