Question

On a multiple choice test with 11 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. Round to the nearest tonth. O A 20.6 OB 2.1 OC. 43 OD 14

Answer 1

a multiple choice test Il questions, each question has four possible answers, one of which is correct. Pe n=11) and probability of correct answer of question is, pa one of option is correct Tokel number of possible answers the - = 0.25 0.25 The variance of the number of correct answer is, Variance = np (1-P) = !1 x 0.25 x C1-0.25) = !1 x 0.25 X 0.75 = 2.0625 variance = 2.1 The correct answer is option ® (B 2.)