AboutScott A Wilson Expertise I can answer any question in general math, algebra, complex mathematics, trigonometry, pre-calculus, probability, statistics, ... is there an end to this list?
Experience Experience in the area; I have tutored people over the years in algebra, basic math, and statistics.
I worked at The Boeing Company for over 5 years.
Education/Credentials: MS degreee in Mathematics from Oregon State Univeristy; taken well over 100 hours of upper division credits in mathematical courses such as calculus, statistics, probabilty, linear algrebra, powers, linear regression, matrices, and more.
I graduated with honors.
Past/Present Clients: College Students at OSU, various math people since college, over 700 people in math and calculus.
Expert: Scott A Wilson Date: 5/14/2008 Subject: probability
Question In a pile of 40 oranges, 10 are rotten. What is the probability of getting at least 3 rotten oranges if 20 oranges are picked at random? Please explain..
Answer If 40 are good and out of them 10 are bad, there are x=40-10 good ones. The odds of getting at least 3 is the same as 1 - (getting 0, 1, or 2). To do each 0,1, or 2, its the sum for n =(0,1,2) of (30 choose 20-n)(10 choose n)/(40 choose 20). Once this is done, subtract the total from 1. This will give you the probability.
Please right again if you need to know how to compute (a choose b) or a continuation of assistance.
You can also right again if you need assistance creating a spreadsheet with the values in it. I will say that if you use a spreadsheet, you will need 3 rows to compute the sum and another row to finish it off (subtract the sum of the 3 results from 1).
Thanks for the question and I look forward to a reply on this or any other question.
