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 2 is less than 24 days?

Respuesta :

Answer:

The probability that the mean lifespan from the sample of 9 houseflies is less than 24 days is 30.85%

Step-by-step explanation:

Given that:

number of samples (n) = 9 houseflies,

Mean (μ) = 26 days,

Standard deviation (σ) = 12 days.

The Z score is used in statistics to know by how much a value is above or below the mean. The Z score (z) is given by the equation:

[tex]z= \frac{x-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex]

To get the probability that the mean lifespan from the sample of 9 houseflies is less than 24 days (i.e x = 24)

[tex]z= \frac{x-\mu}{\frac{\sigma}{\sqrt{n} } }=\frac{24-26}{\frac{12}{\sqrt{9} } } = -0.5[/tex]

From the z table:

P(x < 24) = P(z < -0.5) = 0.3085 = 30.85%

Therefore, the probability that the mean lifespan from the sample of 9 houseflies is less than 24 days is 30.85%

Answer: We cannot calculate this probability because the sampling distribution is not normal

Step-by-step explanation:

it’s the correct answer.