Download T-interval (for unknown population standard deviation)

T­interval (for unknown population standard deviation)
November 29, 2016
Confidence LEVEL vs. Confidence INTERVAL:
95% LEVEL: 95% of the intervals created by taking all possible samples of the same size from the same population and calculating
will contain the true value of the population parameter being estimated.
95% INTERVAL (A, B): We are 95% confident that the true value of the population parameter being estimated is between A and B.
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T­interval (for unknown population standard deviation)
November 29, 2016
Environmentalists, government officials, and vehicle manufacturers are all interested in studying the auto exhaust emissions produced by motor vehicles. The major pollutants in auto exhaust are hydrocarbons, monoxide, and nitrogen oxides (NOX). The table gives NOX levels (in grams/mile) for a sample of light­duty engines of the same type.
Construct a 95% confidence interval for the mean amount of NOX emitted by light­
duty engines of this type.
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T­interval (for unknown population standard deviation)
November 29, 2016
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T­interval (for unknown population standard deviation)
November 29, 2016
Environmentalists, government officials, and vehicle manufacturers are all interested in studying the auto exhaust emissions produced by motor vehicles. The major pollutants in auto exhaust are hydrocarbons, monoxide, and nitrogen oxides (NOX). The table gives NOX levels (in grams/mile) for a sample of light­duty engines of the same type.
Construct a 95% confidence interval for the mean amount of NOX emitted by light­
duty engines of this type.
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T­interval (for unknown population standard deviation)
November 29, 2016
Summary of notation:
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