What Type of Tree Diagram is Needed to Solve this Probability Problem?

[seiferseph]

Here is the problem, I'm having trouble getting started. Do i need a tree diagram? what kind? how do i use it to solve? Thanks in advance!

http://i2.photobucket.com/albums/y15/seiferseph/2.jpg

 

[Jameson]

What is probability?

\frac{desired outcome}{allpossibleoutcomes}

If you don't like to keep the percentages, use and easy number to reference, like 100 people. Remember that the test is skewed. If the test is 95% accurate, how well that affect the testing?

 

[seiferseph]

just got it, thanks.