Question
In: Statistics and Probability
On a multiple choice test with 18 questions, each question has four possible answers, one of...
On
a multiple choice test with 18 questions, each question has four
possible answers, one of which is correct. For students who guess
at all answers, find the variance for the number of correct
answers.
Solutions
Expert Solution
n = 18
p = 0.25
Variance = np(1 - p)
= 18 * 0.25 * 0.75
= 3.375
orchestra answered 2 years agoRelated Solutions
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