SOLUTION: A chimp is taking a multiple-choice test. Of course, the chimp can't read and is guessing for every question. If there are 4 choices for each question, and there are 84 questions o

Question 1111711: A chimp is taking a multiple-choice test. Of course, the chimp can't read and is guessing for every question. If there are 4 choices for each question, and there are 84 questions on the test, How many questions can we expect the chimp to answer correctly? ( there is 25% chance that the chimp will guess correctly)
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A chimp is taking a multiple-choice test. Of course, the chimp can't read and is guessing for every question. If there are 4 choices for each question, and there are 84 questions on the test, How many questions can we expect the chimp to answer correctly? ( there is 25% chance that the chimp will guess correctly)
-----
Binomial Problem with n = 84 and p = 0.25
-----
mean = np = 84(1/4) = 21
------------
Cheers,
Stan H.
--------------------
RELATED QUESTIONS
t = 1/c [ 1n A � 1n(A � N)] describe the time, t, in weeks that it takes to achieve... (answered by stanbon)

One of several Extra Credit Questions, I really need them. Can someone please help? A (answered by stanbon)

The probability of passing a 30 question multiple choice test by randomly guessing the... (answered by ikleyn)

Hey, got referred by an army buddy, can a mathematician give some help on a couple... (answered by lynnlo)

If a student is guessing randomly on a multiple choice test with 4 possible responses per (answered by greenestamps)

If a student is guessing randomly on a multiple choice test with 4 possible responses per (answered by math_tutor2020)

I have an extra credit problem that I really need the points for. Please help me!! A... (answered by stanbon)

1. We know that the probability of correctly responding to a multiple choice question... (answered by stanbon)

Suppose there are 10 items on a true - false test. The person taking the test doesn't... (answered by checkley75)