Example: For the multiple choice test example (10 questions, each with 8 choices), what is the probability that the person gets 2 or 3 questions correct?
X~ binomial (n,p)
Where n = 10, p = 1/8
Binomial probability distribution is
P(X) = nCx px (1-p)n-x
So,
P(X = 2 or 3) = P( X = 2) + p( x = 3)
= 10C2 (1/8)2 (7/8)8+10C3 (1/8)3 (7/8)7
= 0.3336
Example: For the multiple choice test example (10 questions, each with 8 choices), what is the...
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