STATISTICAL TECHNIQUES AND TOOLS
CONFIDENCE INTERVALS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Compute a 90% confidence interval for the situation:A random sample of 30 movie theaters showed that the average price for a movie was $10 with a standard deviation of $1.20.
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(9.71, 10.29)
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(9.934, 10.066)
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(9.64, 10.36)
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(9.628, 10.372)
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Explanation:
Detailed explanation-1: -If the level of confidence is 90%, this means that we are 90% confident that the interval contains the population mean, µ. The corresponding z-scores are ± 1.645.
Detailed explanation-2: -Since 95% of values fall within two standard deviations of the mean according to the 68-95-99.7 Rule, simply add and subtract two standard deviations from the mean in order to obtain the 95% confidence interval.
There is 1 question to complete.