30% of students that take the SAT score over 1200. Let the random variable X represent...
30% of students that take the SAT score over 1200.
Let the random variable X represent the number of students that score over 1200 on the SAT in a random sample of 32 students.
Find the standard deviation of X.(round to 3 decimals places)
Homework Answers
Given that,
p = 0.30
q = 1 - p =1-0.30=0.70
n = 32
standard deviation=
= 
n * p * q =
32*0.30*0.70=2.592
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