The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 8.6 mg and a standard deviation of 1.53 mg. The company that produces these cigarettes claims that it has now reduced the amount of nicotine. The supporting evidence consists of a sample of 31 cigarettes with a mean nicotine amount of 8.023 mg. Assuming that the given mean and standard deviation have NOT changed, find the probability of randomly seleting 31 cigarettes with a mean of 8.023 mg or less. P(M<8.023 mg)%D Based on the result above, is it valid to claim that the amount of nicotine is lower? O Yes. The probability of this data is unlikely to have occurred by chance alone. O No. The probability of obtaining this data is high enough to have been a chance occurrence.

The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 8.6 mg and a standard deviation of 1.53 mg. The company that produces these cigarettes claims that it has now reduced the amount of nicotine. The supporting evidence consists of a sample of 31 cigarettes with a mean nicotine amount of 8.023 mg. Assuming that the given mean and standard deviation have NOT changed, find the probability of randomly seleting 31 cigarettes with a mean of 8.023 mg or less. P(M<8.023 mg)%D Based on the result above, is it valid to claim that the amount of nicotine is lower? O Yes. The probability of this data is unlikely to have occurred by chance alone. O No. The probability of obtaining this data is high enough to have been a chance occurrence.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 9.2 mg and a standard deviation of 1.46 mg. The company that produces these cigarettes claims that it has now reduced the amount of nicotine. The supporting evidence consists of a sample of 47 cigarettes with a mean nicotine amount of 8.795 mg.Assuming that the given mean and standard deviation have NOT changed, find the probability of randomly seleting 47 cigarettes with a mean of 8.795 mg or less.P(M < 8.795 mg) = Based on the result above, is it valid to claim that the amount of nicotine is lower? Yes. The probability of this data is unlikely to have occurred by chance alone. No. The probability of obtaining this data is high enough to have been a chance occurrence.
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