Question

STATISTICS - Probability Rules. Please see IMG:
http://i1084.photobucket.com/albums/j409/QRAWarrior/B22-IMG-004.png

Answer 1

@Callisto

Answer 2

P(M and A) is asking me what is the probability that they are BOTH accepted and that they are BOTH male

Answer 3

The circled number is the number of applicants who are male + accepted. Use it to calculate the probability..

Answer 4

But how do I get the probability for 2 at once?

Answer 5

I know how to get for one. If it was just P(male and accepted), I could do that, but I do not know how to do P(both male and both accepted)

Answer 6

How to do calculate the probability of both male?

Answer 7

P(male and male)? That is (660/800)*(659/799) <-- Sampling without replacement.

Answer 8

You are going to tell me this I believe: Find the P(male and male), find P(accepted and accepted), and then multiply them together?

Answer 9

No!
Total number of male who are accepted = 480
P(both male and accepted) = (480/800) x (479/799)

Answer 10

What?

Answer 11

I believe you did it wrong.

Answer 12

Yes? Can you explain?

Answer 13

Because:
P(both male) = (480/800)*(479/799)


P(male and male) = P(male)*P(male)

If you find one male applicant, then you do NOT want to pick out that same one again randomly, so you remove it.

Answer 14

But now, the condition is P(both male and accepted). We know that to total number of male who are accepted is 480 (from the chart)
So,
P(both male and accepted) = P(male and accepted) x P(male and accepted)
= (480/800) x (479/799)

Answer 15

Here is a simple example:
- Suppose there are 3 gold rooms, 2 silver rooms and 3 bronze rooms. You get to pick first and you end up getting the gold room:

The probability of getting a gold room for you was 3/8
Now, the probability that your friend can get a good room is 2/7 <-- BECAUSE we HAVE 7 rooms left over now.

Answer 16

I understand what you said

Answer 17

But, you still have to use sampling without replacement there so you do not end up getting that same accepted male again

Answer 18

And you did it

Answer 19

I just checked now the last few numbers

Answer 20

OHHH

Answer 21

So you did this:

P( (male and accepted) and (male and accepted))

Answer 22

No

Answer 23

I meant

Answer 24

P(both male and accepted) = P( (male and accepted) and (male and accepted)) ......

Answer 25

So THAT is how you rearrange those two. I will remember that.

Answer 26

Thank you for your help.

Answer 27

Welcome... Hope you understand it....

Answer 28

@Callisto I have another probability problem.