math questiomn-easy??...?
there are 2 white marbles,4 red marbles,and 6 blue marbles in a bag.Once a marble is selected it is not replaced.Find the probability that 2 red marbles are chosen.
A.) 1/11
b.) 2/11
c.) 2/11
D.) 4/11
please explain how to do this...i dont understand it
Update:thx manda =]
More Questions From This User See All
Answers & Comments
Verified answer
It's the probability of choosing one red ball from 12 balls, then another red from the remaining 11 balls...
These are independent events...
Thus P = (4 / 12) * (3 / 11) = 1/11
12 total marbles so 4/12 (or1/3) prob that first is red
now 11 marbles only 3 red so 3/11 prob second one is red
1/3 times 3/11 =3/33=1/11 which is your answer