1. Aim: How do we find probability using Pascal’s triangle? Do Now: If a coin is tossed two times, what is the probability you will get 2 heads?

3. How to Construct Pascal’s Triangle 1)At the tip of the triangle, there is a number one. This makes up the 0 th row. 2)The next or first row contains two ones, which are formed by adding the two numbers above them to the left and right. In this case each one is formed by adding 1 and 0. All numbers outside the triangle are considered to be zero. *Note that all the rows in your triangle start and end in 1. 3) To create the second row, you do the same: 0+1=1, 1+1=2 and 1+0=1. So the numbers in this row are 1,2 and 1. 4) For the next rows you do the same.

4. Formula n*X X = the probability the combination will occur. n= The Pascal number that corresponds to the ratio you are looking at.

5. If you flip a coin 3 times, what is the probability that you will get 2 heads and 1 tails?

6. A couple has decided to have 4 children. What is the probability that they will have 2 boys and 2 girls?