The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 0.924 g and a standard deviation of 0.289 g. The company that produces these cigarettes claims that it...

The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 0.924 g and a standard deviation of 0.289 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 36 cigarettes with a mean nicotine amount of 0.861 g.


Assuming that the given mean and standard deviationhave NOT changed, find the probability of randomly seleting 36 cigarettes with a mean of 0.861 gor less.
P(x-bar< 0.861="" g)="">
Enter your answer as a number accurate to 4 decimal places.


Based on the result above, is it valid to claim that the amount of nicotine is lower?