A bag contains 8 marbles. Four are blue, three are green, and one is orange. You draw out one marble and then another, without replacing the first marble. Find the probability of drawing two blue marbles.

ill post the answer choices in a second

Question

A bag contains 8 marbles.  Four are blue, three are green, and one is orange.  You draw out one marble and then another, without replacing the first marble.  Find the probability of drawing two blue marbles.


ill post the answer choices in a second

anonymous · Answer

1/2

1/4

3/14

3/28

anonymous · Answer

3/28

amistre64 · Answer

P(B|B) might be the technical definition of it

amistre64 · Answer

4/8 * 3/7  is what my first thought was, but there is a hypergeometric formula that might be more astute

amistre64 · Answer

$$p=\frac{\binom{N-M}{n-x}\binom{M}{x}}{\binom{N}{n}}$$

amistre64 · Answer

N=8; M=4; n=2 drawn; and x=2 success  if i read it right

amistre64 · Answer

which of course is the same thing i thought to begin with :)

so yeah