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Finding probabilities with sample means

You might need: Calculator,Z table


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 x¯ is less than 24 days?
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