Question

Balls

Answer 1

Oh this is nice

Answer 2

I wonder what this is going to be

Answer 3

cool beans

Answer 4

There are 3 red and 2 white balls in one box. There are 4 red and 5 white balls in a second box. You select a ball at random, it is red. What are the odds that it came from the second box.

Answer 5

i was in the gutter

Answer 6

better than sewer :) GL

Answer 7

This is torture o.o worse than finding the probability of something

Answer 8

intuitively I am thinking it would just be (# of red balls in second box)/(# of total red balls) since this is a conditional probability

Answer 9

that doesn't take into account the relative probabilities of getting red in each box though

Answer 10

its asymetrical

Answer 11

\(P(\text{Red}) = \left( \dfrac{1}{2} \times \dfrac{3}{5} \right) + \left( \dfrac{1}{2} \times \dfrac{4}{9} \right) = \dfrac{47}{90}\)

\(P(\text{Red from 2nd Box}) = \dfrac{1}{2} \times \dfrac{4}{9} = \dfrac{4}{18}\)

Meaning that:

\(P(\text{Red}) = \dfrac{94}{\color{red}{180}}\)

\(P(\text{Red from 2nd Box}) = \dfrac{40}{\color{red}{180}}\)


Which is 180 random walks.....

so \(P(\text{Red from 2nd Box} | \text{Red}) = \dfrac{40}{94} = \dfrac{20}{47}\)

Answer 12

It was a great question, ruined by the usual white noise.