# If 80% of the applicants are able to pass a driver's proficiency road test, how do you find the mean, variance, and standard deviation of the number of people who pass the test in a sample of 300 applicants?

If 80% of the applicants are able to pass a driver's proficiency road test, how do you find the mean, variance, and standard deviation of the number of people who pass the test in a sample of 300 applicants?
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neglegir86
Expected value of X, $Mean=\mu =np=300\ast 0.8=240$
Mean is: $\mu =240$
Variance: ${\sigma }^{2}=np\left(1-p\right)=300\ast \left(0.8\right)\left(1-0.8\right)=48$
Variance: ${\sigma }^{2}=48$
Std Dev: $\sigma =\sqrt{{\sigma }^{2}}=\sqrt{48}\approx 6.928203\approx 6.928$
Standard deviation: $\sigma =6.928$