SOLUTION: If you are not prepaired for a test and you have 3 true or false questions what is the probablity of getting 2 out of the 3 correct?

Question 544597: If you are not prepaired for a test and you have 3 true or false questions what is the probablity of getting 2 out of the 3 correct?

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
If you are not prepaired for a test and you have 3 true or false questions what is the probablity of getting 2 out of the 3 correct?
-----
Binomial Problem with n = 3 and p(correct) = 1/2
---
P(x = 2 or 3) = P(2) + P(3)
= 3C2(1/2)^3 + 3C3(1/2)^2
----
= (3+1)(1/2)^3
----
= 4/8
---
= 1/2
============
Cheers,
Stan H.
==============
RELATED QUESTIONS
If you have a true/false test with 4 questions on it if you guess what is the probability (answered by Susan-math)

On a 5 question true or false test what is the probability of getting two right if you... (answered by greenestamps)

A.How many different ways are there to answer a true/false test that has four questions? (answered by stanbon)

You are taking a true-false test that has ten question, and you need a score of 70... (answered by stanbon)

You are taking a test that has 5 true/false questions. If you answer each question with... (answered by ewatrrr)

If you take a mulitple choice test with 25 problems each having four answers options what (answered by checkley77)

Solve. There are 10 true/false questions on a test. You do not know the answer to 4 of... (answered by ewatrrr)

a true/false test has 10 questions each of which has 2 possible answers, only one of... (answered by ewatrrr)

what is the probability of getting 3 true or false questions right..and i need a sample... (answered by ewatrrr)