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Houseflies have pretty short lifespans. Males of a certain species have lifespans that are strongly skewed to the right with a mean of

26

days and a standard deviation of

12

days. A biologist collects a random sample of

9

of these male houseflies and observes them to calculate the sample mean lifespan.

What is the probability that the mean lifespan from the sample of $9$ ‍ houseflies $\bar{x}$ ‍ is less than $24$ ‍ days?

Statystyka i prawdopodobieństwo