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singh2010
Apr 30, 2010, 06:57 AM
Attended Did not attend

Got job desired
120 30
Did not get job desired
40 60

1. Given that a student attended the careers service, what is the probability that a randomly selected student got the job they desired?

2. Given that a student attended the careers service, what is the probability that a randomly selected student did not got the job they desired?

3. Do you think that attendance at the careers service improves a student's chance of getting the job they desired? Can you give another reasonable explanation for these statistics?

I still don't know which probabilty method I would use for these questions. Can someone help, thanks.

And sorry for the way I did the small figures at the top, don't know how to sort that out either lol.

ebaines
Apr 30, 2010, 07:28 AM
It's not as hard as it sounds. Take it one step at a time.

"Given that a student attended the careers service" means you only need to look at that first column of data. Of those that attended, 120 got a job and 40 did not. You calculate the probability of something occurring by dividing the number of times the thing did occur by the number of chances there were for it to occur. There were a total of 160 attendees (120+ 40) so there were 160 chances for people to get a job. Thus the probability of getting a job for those who attended is 120/160 = 3/4.

Now - can you complete the rest?

singh2010
Apr 30, 2010, 07:36 AM
Lol I feel like an idiot now that you broke it down like that, I was just confused because I thought you would have to use one of the probability formulas but thanks for the help.