Total number of ways of selecting 2 apples is 5C2 = 10
Of which, one is rotten. This means that out of 4 apples there is a rotten fruit (There is 1 good apple out of 2 selected apples). That means, total ways of having a spoiled fruit is 4.
Probability that 2 selected apples will include a spoiled one is 4/10 = 2/5 (Choice C)
700+ spoiled apples
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sadullaevd
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Hi Munaf,
Here as per my understanding this question can be solved in this way:
Henry picks 2 apples from 5 apples in the basket so total possible ways is:5c2= 10.
Possibility that 2 selected apples include spoiled one is (Probality of getting one spolied one + Probability of getting one good one from the 4 apples)
this probability will be 1 + 4c1 = 5
Hence the probability of getting one spoiled among the two apples picked randomly is 5/10 = 1/2.
Rgds,
AVR.
Here as per my understanding this question can be solved in this way:
Henry picks 2 apples from 5 apples in the basket so total possible ways is:5c2= 10.
Possibility that 2 selected apples include spoiled one is (Probality of getting one spolied one + Probability of getting one good one from the 4 apples)
this probability will be 1 + 4c1 = 5
Hence the probability of getting one spoiled among the two apples picked randomly is 5/10 = 1/2.
Rgds,
AVR.
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papgust
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You select 2 apples out of 5. Out of those 2, 1 is a good fruit. The other is the rotten fruit.munaf wrote:How you got 4 in the numerator..some one please explain.
Number of ways of choosing that rotten fruit is 4C1 = 4 (No. of ways to select a rotten fruit out of 4 apples. We are not taking the 5th apple into account because we have already chosen that 5th fresh apple)
I hope this is clear!
Try this way. 1 minus the chance of getting no rotten apples
1)chance of getting no rotten apples
1 1st chance is 4/5
2nd chance is 3/4
then multiply (3/4)(4/5) = 12/20
1- (12/20) = 8/20 (chance of not getting a rotten apple) =4/10 = 2/5
1)chance of getting no rotten apples
1 1st chance is 4/5
2nd chance is 3/4
then multiply (3/4)(4/5) = 12/20
1- (12/20) = 8/20 (chance of not getting a rotten apple) =4/10 = 2/5
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maihuna
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Simultaneously doen't mean anything: Out of 2-picks one should be spoiled one: can be done in : 2*(4/5)*(1/4) = 2/5munaf wrote:16) A basket has 5 apples, one is spoiled. If Henry picked 2 apples simultaneously and at random, what is probability that the 2 selected apples will include the spoiled one.
a. 1�5
b. 2�10
c. 2�5
d. 1�2
e. 3�5
Charged up again to beat the beast 
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homersimpson
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This should be as stated in many posts above:
(1C1 x 4C1)/ 5C2
1C1 = number of ways you can take out one rotten apple
4C1 = number of ways you can take out one fresh apple out of 4
5C2 = number of ways you can take out 2 apples out of 5.
Cheers
(1C1 x 4C1)/ 5C2
1C1 = number of ways you can take out one rotten apple
4C1 = number of ways you can take out one fresh apple out of 4
5C2 = number of ways you can take out 2 apples out of 5.
Cheers
