Answer:
The standard deviation is of 7.22 people.
Step-by-step explanation:
For each person, there are only two possible outcomes. Either they have the mutation, or they do not. The probability of a person having the mutation is independent of any other person, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x successes on n repeated trials, with p probability.
The expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
About 7% of the population has a particular genetic mutation.
This means that [tex]p = 0.07[/tex]
800 people are randomly selected.
This means that [tex]n = 800[/tex]
Find the standard deviation for the number of people with the genetic mutation in such groups of 800.
[tex]\sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{800*0.07*0.93} = 7.22[/tex]
The standard deviation is of 7.22 people.