The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 0.967 g and a standard deviation of 0.286 g. The company that produces these cigarettes claims that it has now reduced the amount of nicotine. The supporting evidence consists of a sample of 44 cigarettes with a mean nicotine amount of 0.881 g. Assuming that the given mean and standard deviation have NOT changed, find the probability of randomly seleting 44 cigarettes with a mean of 0.881 g or less. P(M < 0.881 g) = Enter your answer as a number accurate to 4 decimal places. NOTE: Answers obtained using exact z-scores or z-scores rounded to 3 decimal places are accepted. Based on the result above, is it valid to claim that the amount of nicotine is lower? No. The probability of obtaining this data is high enough to have been a chance occurrence. Yes. The probability of this data is unlikely to have occurred by chance alone.
The amounts of nicotine in a certain brand of cigarette are
Assuming that the given mean and standard deviation have NOT changed, find the probability of randomly seleting 44 cigarettes with a mean of 0.881 g or less.
P(M < 0.881 g) =
Enter your answer as a number accurate to 4 decimal places. NOTE: Answers obtained using exact z-scores or z-scores rounded to 3 decimal places are accepted.
Based on the result above, is it valid to claim that the amount of nicotine is lower?
- No. The probability of obtaining this data is high enough to have been a chance occurrence.
- Yes. The probability of this data is unlikely to have occurred by chance alone.
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