# Math Help - probability question

1. ## probability question

To determine whether a single coin is fair, the coin was tossed 200 times. The observed
frequencies with which each of the two sides of the coin turned up are recorded as 110 heads
and 90 tails. Is there sufficient evidence at the 5% significance level to allow you to conclude
that the coin is not fair?

2. Originally Posted by heidigirl

To determine whether a single coin is fair, the coin was tossed 200 times. The observed
frequencies with which each of the two sides of the coin turned up are recorded as 110 heads
and 90 tails. Is there sufficient evidence at the 5% significance level to allow you to conclude
that the coin is not fair?
Calculate the probability of seeing 110 or more heads given that the coin is fair. Is it less than 0.05?

3. Hi,

That problem you have is testable with a binomial distribution.
I have just been reading up on binomial distribution and your example is mostly given in textbooks then.

With the binomial distribution you can find out the probibilty is to reach 110 times heads and 90 times tails. Then there is a confidence limit and level for that kind of distribution.

Hope that helps. Of course you got to read up something. But it is not as complicated as it sounds.

Sts