The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 0.942 g and a standard deviation of 0.317 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 42 cigarettes with a mean nicotine amount of 0.888 g. Assuming that the given mean and standard deviation have NOT changed, find the probability of randomly selecting 42 cigarettes with a mean of 0.888 g or less.
P(M < 0.888 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? (Let’s use a 5% cut-off for our definition of unusual.)
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.