SOLUTION: <b> Solve using whatever counting methods are necessary. Please show work.</b> A box contains 5 red marbles and 7 black marbles. You draw 4 marbles randomly from the box. What i

Question 35053: Solve using whatever counting methods are necessary. Please show work.
A box contains 5 red marbles and 7 black marbles. You draw 4 marbles randomly from the box. What is the probability that you will draw 3 red marbles and 1 black marble in any order?

Answer by longjonsilver(2297) (Show Source): You can put this solution on YOUR website!
4 options:
RRRB
RRBR
RBRR
BRRR

Look at RRRB ans assuming there is no replacement of marbles during this process:
First out is red: P = 5/12
second out is red: P = 4/11
third out is red: P = 3/10
fourth out is black: P = 7/9

--> P =

Now look at RRBR:
--> P =
which if you look closely is the same thing as RRRB

So, in total we have 4 versions of the same thing
--> P =
--> P =
--> P =
--> P =
--> P =
--> P =
--> P = 0.141414

jon.

RELATED QUESTIONS
Solve using whatever counting methods are necessary. Please show work. A box... (answered by venugopalramana)

Solve using whatever counting methods are necessary. Please show work. How... (answered by longjonsilver)

A box contains 12 red marbles, 7 green marbles, and 9 black marbles. A sample of 9... (answered by stanbon)

a box contains 10 marbles 7 of which are black and 3 are red . if 3 marbles is drawn at... (answered by ewatrrr,ikleyn)

A box contains ten marbles, seven of which are black and three are red. Three marbles... (answered by VFBundy)

Urn A contains 4 red and 3 black marbles. Urn B contains 5 red and 7 black marbles. From... (answered by greenestamps)

A jar contains marbles in the ratio of 11 red to 5 black. If there 230 black marbles, how (answered by erica65404,stanbon)

Hi The number of marbles in box A is half the number in box B. All the marbles in box A... (answered by ikleyn)

A box contains 6 red marbles, 10 white marbles, 18 blue marbles and 5 black marbles. What (answered by howcutegirl)