# Question

A television sports commentator wants to estimate the proportion of Americans who “follow professional football.”What sample size should be obtained if he wants to be within 3 percentage points with 95% conﬁdence if

(a) He uses a 2010 estimate of 53% obtained from a Harris poll.

(b) He does not use any prior estimates?

(c) Why are the results from parts (a) and (b) so close?

(a) He uses a 2010 estimate of 53% obtained from a Harris poll.

(b) He does not use any prior estimates?

(c) Why are the results from parts (a) and (b) so close?

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