MATH SOLVE

4 months ago

Q:
# A television sports commentator wants to estimate the proportion of citizens who "follow professional football." Complete parts (a) through (c). What sample size should be obtained if he wants to be within 4 percentage points with 96% confidence if he uses an estimate of 48% obtained from a poll? What sample size should be obtained if he wants to be within 4 percentage points with 96% confidence if he does not use any prior estimates? Why are the results from parts (a) and (b) so close?

Accepted Solution

A:

Answer:626 and 654Step-by-step explanation:Given that a television sports commentator wants to estimate the proportion of citizens who "follow professional football."Part I:p = 0.48[tex]q=1-p = 0.52\\se = \sqrt{\frac{pq}{n} } \\\frac{0.4996}{\sqrt{n} } =[/tex]Margin of error =[tex]2.045*\frac{0.4996}{\sqrt{n} }<0.04\\n>626[/tex]Sample size should be >626Part II:If unknown we take p = 0.5 because maximum std error for thisHere everything would be the same except insted of 0.48 we use 0.5Margin of error = [tex]2.045*\sqrt{\frac{0.5}{\sqrt{n} } } <0.04\\n>654[/tex]-------------------------a and b are too close because 0.46 proportion is close to part b proporti0n 0.5