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## #1 2013-04-30 05:47:37

jasminM01
Guest

### Help!! Probability

Selena took the same test that linda did, but she guessed on all of the questions. if there were 64 questions, what is the probability that she got at least 20 questions right. if she needed to get 35 correct in order to pass the test, what would you think of her chances of passing by guessing on all of the questions?

I need step by step instructions on how to solve this please!

## #2 2013-04-30 05:55:34

bobbym

Offline

### Re: Help!! Probability

Hi;

Again, this is a binomial distribution. We can calculate this and we can estimate it.

Let's calculate first.

I do not like her chances.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #3 2013-04-30 08:07:01

zetafunc.
Guest

### Re: Help!! Probability

Do you know how to approximate a binomial distribution with a normal distribution, jasminM01?