Math Math Math.. (I forgot the name of the lesson)

BELLRINGER

Create a decision tree for:

Probability it will snow is .75
If it snows, the probability that I will ski is .9
Probability I will ski if it doesn't snow is .2
Find the Probability that I will ski


ANSWER: 29/40


SOLUTION:



Ski .9
/
.75 Snow
/ \
/ .1 No Ski
/
.25 No Snow /-- .2 Ski
/ \/
/
.8 No Ski


To find the probability of skiing you:

1. Multiply the .75 probability of snow X the .9 of skiing if there's snow which equals .675 and put into fraction form is 27/40.
2. Multiply the .25 probability of no snow X .2 of skiing without snow and that equals 2/40.
3. Multiply the .1 probability of not skiing with snow X .75 of snow which equals 3/40.
4. Multiply one last time the .25 probability of no snow X not skiing without snow and that equals 8/40.
5. Then you add 27/40 + 2/40 and that equals 29/40, which is the probability you will ski.



AGENDA

I. Bell Ringer
II. Review Homework
III. Probability w/ Venn Diagram
IV. Schedule for Math IA




Objective:
Student will be able to use Venn Diagram to illustrate real world situations and find a probability.




Question:
Bob lives in a house. Everytime it rains heavily his basement floods and he has to take out buckets of water. Probability it will rain heavy is .4. Probability it won't rain is .6. Probability he won't take out buckets of water if there's no rain is .6.
What is the probability he will take out buckets of water?



Ahh. I know this is a little late.. I barely got home half an hour ago. Easiest question I could come up with.. lol.
Have fun. The tree looked better before I posted it.