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.