The Coca-cola Company has 40% of the cola market. The probability that a sample proportion for n=30 falls within 0.10 of the true population proportion of .40, which represents the proportion of cola drinkers who prefer a coca-cola drink is?
The Coca-cola Company has 40% of the cola market. The probability that a sample proportion for n=30 falls within 0.10 of the true population proportion of .40, which represents the proportion of cola drinkers who prefer a coca-cola drink is?
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Solve the above equation for the critical value and hence get the value of . Use this value to get the required probability.
eg. If then (using tables) and so the required probability would be 0.95.