SOLUTION: Beth is taking a ten-question multiple-choice test for which each question has three answer choices, only one of which is correct. Beth decided on answers by rolling a fair die an

Algebra.Com
Question 995499: Beth is taking a ten-question multiple-choice test for which each question has three answer choices, only one of which is correct. Beth decided on answers by rolling a fair die and marking the first answer choice if the die shows 1 or 2, the second if it shows 3 or 4, and the third if it shows 5 or 6. Find the probability of

a) exactly four correct answers
b) fewer than three correct answers

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Beth is taking a ten-question multiple-choice test for which each question has three answer choices, only one of which is correct. Beth decided on answers by rolling a fair die and marking the first answer choice if the die shows 1 or 2, the second if it shows 3 or 4, and the third if it shows 5 or 6.
------------------
Binomial Problem with n = 10 and p(correct) = 1/3
=========
Find the probability of
a) exactly four correct answers
P(x = 4) = 10C4(1/3)^4*(2/3)^6 = binompdf(10,1/3,4) = 0.2276
---------------------------
b) fewer than three correct answers
P(0<= x <= 2) = binomcdf(10,1/3,2) = 0.2991
------------
Cheers,
Stan H.
---------------

RELATED QUESTIONS

A multiple-choice test has 6 questions. Each question has 5 choices and only one of which (answered by ikleyn)
In how many ways can you answer a twelve-question multiple-choice test, in which each... (answered by ikleyn)
A student is taking a multiple choice exam in which each question has five choices.... (answered by stanbon)
a multiple choice test has 6 question each of which has possible answers only one of... (answered by ewatrrr)
A student guesses blindly on a 20-question multiple choice test. If each question has 4... (answered by stanbon)
A student who has not studied for a multiple-choice test decides to guess the answers for (answered by math_helper)
A multiple choice test consists of five questions, each of which has four choices. Each... (answered by solver91311)
You are taking a multiple choice test containing 60 questions. Each question has 5... (answered by Boreal)
nicoles is taking a 5 question multiple choice test. if she completely guesses every... (answered by ewatrrr)