Posted by **Danielle** on Friday, December 14, 2007 at 12:44pm.

I do not understand the binomial theorem. One of my questions is "there are 5 mutiple choice questions with 4 possible answers each. What is the probability of getting more than 3, exactly 3, and less than 3 correct?"

Thanks for any help:)

- math-binomial prob -
**drwls**, Friday, December 14, 2007 at 1:18pm
Use the binomial theorem to get the possibility of 0,1,2,3,4 and 5 correct.

For zero correct, the probability is just (3/4)^5 = 0.2373. 3/4 is the probability of getting each one wrong.

For five correct, the probability is

(1/4)^5 = 0.0001

For one correct, (one success and 4 failures) the probability is

5!/[1!*4!]*(1/4)*(3/4)^4

= 5(.25)(.3164) = 0.3955

(That is where you need the binomial theorem)

For two correct, using the same theorem, the probability is

[5!/(3!*2!)](1/4)^2*(3/4)^3

= 10*(0.25)^2(0.4219)= 0.2637

For three correct, the probability is

5!/[2!*3!)](1/4)^3*(3/4)^2 = 0.0879

For four correct, the probability is

(5!/4!)(1/4)^4*(3/4)= 5*.0039*.3164 = 0.0195

Use these results to get the probabilities for >3 and <3 right.

- math-binomial prob -
**abbas**, Sunday, January 24, 2016 at 12:14pm
Use binomial the porem to expand (x+y) 25

- mth111 -
**abbas**, Sunday, January 24, 2016 at 12:20pm
Use binomial the porem to expand (x+y) 25

## Answer This Question

## Related Questions

- statistic - Quiz has 6 questions. Each question has five possible answers, only ...
- Math Binomial theorem - I'm preparing for a test and one of the questions in my ...
- Statistics - A multiple choice test has five choices. Therefore the probability ...
- math data management - a multiple choice quiz has 10 questions. each question ...
- Math - There is a 100 question multiple choice test each with 5 choices. You ...
- statistics - A multiple choice test has 20 questions with each having 4 possible...
- Math - 10 multiple choice questions each with three possible answers only one of...
- Statistics Algebra 2 - A 10-question multiple choice test has 4 possible ...
- Math - I am not sure which questions I got wrong but I am not getting the link ...
- Probability - You are taking a multiple choice test that has 20 questions with 4...

More Related Questions