Answer:
Expected children nearsighted = 20.28 children
Standard deviation = 4.22 children
Step-by-step explanation:
This is an example of a binomial distribution. The expected number of children affected by nearsightedness is given by the total population multiplied by the rate of succes (being affected by nearsightedness):
[tex]n=169*0.12\\n=20.28\ children[/tex]
In a binomial distribution, the standard deviation is given by:
[tex]\sigma = n*p*(1-p)\\\sigma = \sqrt{169*0.12*(1-0.12)}\\\sigma=4.22\ children[/tex]
