Four balls in a bag respectively are red, blue, yellow, and

Question

Four balls in a bag respectively are red, blue, yellow, and green. If two balls are selected at random, what is the probability that one of them is green or blue?

rxs0005 · Answer

ANS : 1/2 

Let the non blue or green colors be rep by X the various possbilities are

XB + BX + XG + GX + BG + GB 

in terms of probability it is 

6 * ( 1/4 * 1 / 3 ) = 1/2

sparky · Answer

5/6

1- prob(red&yellow) = 1 - 1/4c2 = 5/6

christoph · Answer

gr gb gy rb ry rg br by bg yr yg yb => 10/12 or 5/6

Antmavel · Answer

Also found 5/6

total possible couples : (4*3)/2 = 6
couples of balls with G : GY, GB, GR
couples of balls with B (other than GB) : BY, BR
total positive outcomes (couples G + couples B) / total possible couples
5/6

meenu · Answer

I assumed the ques is at least 1 blue or 1 green. 

With that I got 5/6

1 - 1/4 * 1/3 * 2 = 1 - 1/6 = 5/6

BG · Answer

Agree with 1/2 .We have 4 balls, the prob of taking B OR G is 1/4+1/4=1/2

tkirk32 · Answer

1 - prob(RedvYellow)

RY = 1/12
YR = 1/12

1/12 + 1/12 = 1/6

1- (1/6) = 5/6

HIMALAYA · Answer

4c2=(4x3x2)/(2x2) = 6
green= 1 (3c2)= 3
blue= 1 (3c2)= 3
one of them is green or blue = 3+3-1(common in both)=5
the prob = 5/6

greenandwise · Answer

questions asks green or blue not green and blue therefore:

Probablility blue = 1/4

Probability green = 1/4

Prob green or blue = 1/4 +1/4 = 1/2

Don't see where 5/6 comes from...But then again maybe I'm way off here...

HongHu · Answer

You are taking two balls, not one ball, greenandwise. That's why you can just add the two 1/4 together.

Basically this question is asking what is the probability that you will get no Red and no White when you draw two balls from the four.

So it would be 1-1/C(4,2)=5/6.

ashkg · Answer

Total outcomes = 4C2 = 6

P(G OR B ) = P(G) + P(B) - P(G AND B )

P(G) = 3/6
P(B) = 3/6
P(G AND B) = 1/6

= 3/6 +3/6 - 1/6
= 5/6

vivian003096 · Answer

P(G or B) first time= 2/4
+
P(G or B) second time=1/3

So  P=5/6

cloudz9 · Answer

when the question states that one of them is green or blue does that mean only one or at least one i assumed it means only one and got an answer of 2/3 however others have assumed at least one, thus including the possibility of getting green and blue and getting an answer of 5/6 please clarify about how to make a distiction thnx

HongHu · Answer

If it says one of two is such and such then the other one could be anything. If it is "exactly one" then the question must have the word "exactly" in there.

Four balls in a bag respectively are red, blue, yellow, and

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