# Math Help - probability outcomes about coin flips

1. ## probability outcomes about coin flips

Here's my homework question:

A woman flips a coin exactly 6 times in a row. What is the probability that the coin turned heads up exactly 3 times.

Can you show me as much work as you can and explain the steps to me?

Thank you.

2. What have you learned about probability so far? Have you learned about binomial distribution?

3. Yes, we have discussed binomial distribution.

4. Then you would know that:

The number of the particular outcome (3 heads) is
$^nC_k p^k (1-p)^k$

p is the probability of getting heads on 1 flip, so it's 0.5
k is the number of times p will occur, so it's 3
n is the number of times you repeat the process, so it's 6.

This gives you the number of ways 3 heads can be obtained from 6 coin flips.

Now you will need to divide this number by the number of total different outcomes to find the probability.