Math Is Fun Forum

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!

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

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.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

zetafunc.

Guest

Re: Help!! Probability

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