A multiple choice quiz consists of 7 questions each with 5 p

A multiple choice quiz consists of 7 questions, each with 5 possible answers. If a student guesses at the answer to each question, then the mean number of correct answers is?

A multiple choice quiz consists of 7 questions, each with 5 possible answers. If a student guesses at the answer to each question, then the standard deviation for the number of correct answers is?

Solution

Here,

n = 7

and the probability of a correct answer is

p = 1/5 = 0.2

a)

A multiple choice quiz consists of 7 questions, each with 5 possible answers. If a student guesses at the answer to each question, then the mean number of correct answers is?

u = mean = np =    1.4   [ANSWER]  

b)

A multiple choice quiz consists of 7 questions, each with 5 possible answers. If a student guesses at the answer to each question, then the standard deviation for the number of correct answers is?

s = standard deviation = sqrt(np(1-p)) =    1.058300524   [ANSWER]