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• February 2nd 2009, 07:18 PM
jax760
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Because of the populaity of movies as an entertainment medium for college students, you plan to do a national study of the average cost of a movie ticket. If you assume that the standard deviation of the population = $0.50, what samle size would you have to take to be 95% confident that your estimate was within$0.25 of the true mean ticket prices?
• February 3rd 2009, 03:57 AM
mr fantastic
Quote:

Originally Posted by jax760
Because of the populaity of movies as an entertainment medium for college students, you plan to do a national study of the average cost of a movie ticket. If you assume that the standard deviation of the population = $0.50, what samle size would you have to take to be 95% confident that your estimate was within$0.25 of the true mean ticket prices?

Solve $0.25 = 1.96 \left( \frac{0.50}{\sqrt{n}} \right)$ for $n$.