A small liberal arts college in the Northeast has 350freshmen. One hundred five of the freshmen are female. Suppose sixty freshmen are randomly selected (without replacement).Step 2 of 2:Find the standard deviation of the number of females in the sample. Round your answer to two decimal places, if necessary.

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Answer:

The standard deviation of the number of females in the sample is 3.21.

Step-by-step explanation:

For each freshmen, there are only two possible outcomes. Either it is a female, or it is not. Sixty freshmen are randomly selected (without replacement). This means that the hypergeometric distribution is used to solve this question.

Standard deviation of the hypergeometric distribution:

We have that:

N is the population size.

n is the sample size.

s is the number of successes in the sample.

The standard deviation is given by:

[tex]\sigma = \sqrt{n(\frac{s}{N})(1 - \frac{s}{N})(\frac{N - n}{N-1})}[/tex]

A small liberal arts college in the Northeast has 350freshmen.

This means that [tex]N = 350[/tex]

One hundred five of the freshmen are female.

This means that [tex]s = 105[/tex]

Suppose sixty freshmen are randomly selected

This means that [tex]n = 60[/tex]

Find the standard deviation of the number of females in the sample.

[tex]\sigma = \sqrt{60(\frac{105}{350})(1 - \frac{105}{350})(\frac{350 - 60}{350 -1})} = 3.21[/tex]

The standard deviation of the number of females in the sample is 3.21.