HELP ,(bayes theorem)

[lorik]

1. The problem statement, all variables and given/known data
bayes theorem
we got 5 boxes with white and black balls ,2 boxes have 2 white balls and 3 black(H1), 2 boxes have 1 white and 4 black(H2) , 1 box has 4 whites and 1black(H3) .From a random extraction the ball turned out to be black find probability that the extracted ball was from the second box

p(H1)=2/5 ,p(H2)=2/5, p(H3)=1/5 ,ph1(A)=3/5, Ph2(A)=4/5, ph3(A)=1/5

This is the way its written in the book and professor taught us as its written in the book




2. Relevant equations

p(h1)=2/5 ,p(h2)=2/5, p(h3)=1/5 ,ph1(A)=3/5, Ph2(A)=4/5, ph3(A)=1/5 <------ Is this equation mistakenly typed ?
Thats all Im asking PLEASE DONT ASK WHAT IS ,P ,H ,OR A coz they dont matter AT ALL !!!!!

3. The attempt at a solution
I asked this question some time ago but all you did was ask whats ,P,A etc
thanks to all who help

[zhermes]

Wait, what's A?

[vela]

1. The problem statement, all variables and given/known data
bayes theorem
we got 5 boxes with white and black balls ,2 boxes have 2 white balls and 3 black(H1), 2 boxes have 1 white and 4 black(H2) , 1 box has 4 whites and 1black(H3) .From a random extraction the ball turned out to be black find probability that the extracted ball was from the second box

p(H1)=2/5 ,p(H2)=2/5, p(H3)=1/5 ,ph1(A)=3/5, Ph2(A)=4/5, ph3(A)=1/5

This is the way its written in the book and professor taught us as its written in the book

2. Relevant equations

p(h1)=2/5 ,p(h2)=2/5, p(h3)=1/5 ,ph1(A)=3/5, Ph2(A)=4/5, ph3(A)=1/5 <------ Is this equation mistakenly typed ?
Thats all Im asking PLEASE DONT ASK WHAT IS ,P ,H ,OR A coz they dont matter AT ALL !!!!!

3. The attempt at a solution
I asked this question some time ago but all you did was ask whats ,P,A etc
thanks to all who help
The problem is you're asking us if what was typed makes sense without giving us all the info. It's like forming a sentence with a bunch of words and asking if it makes sense without knowing the meaning of the words. How are we supposed to know?

I can take a guess as to what A, ph1, ph2, and ph3 stands for, and if I'm right, what's written would be correct. Why do you think there's a mistake?

[lorik]

@vela

then why do you think p(h2) is 2/5 ? Isn't there 1 white in the second box ? Same goes for H3 as its written 4 whites and p(h3) is showing 1/5 :confused:

[vela]

What's the difference between when you wrote p(h1) and ph1(A)? What do they represent?

[lorik]

What's the difference between when you wrote p(h1) and ph1(A)? What do they represent?

p(h1) is for whites and ph1(A) is for blacks ?

[vela]

No. I get the feeling you're just making wild guesses. Try reading your book and notes to figure out what the notation means.

[lorik]

No. I get the feeling you're just making wild guesses. Try reading your book and notes to figure out what the notation means.

I have and so far its impossible to understand this particular problem ,book i have sucks

[lorik]

Well I think I got it the idea just came out of nowhere ph1,ph2,ph3 have their number 2/5 ,2/5 ,1/5 because when looking at the exercise it clearly says 2 boxes ,2 boxes and then finally says 1 box ,while ph1(A) have their numbers acquired from black balls ,at least thats how i understand it ,if im correct please let me know :smile:

[vela]

Yes, that sounds right!