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Re: A bag contains 3 yellow and 5 blue equally sized marbles. Tw [#permalink]
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Farina wrote:
I dont understand the solution sorry :(
It says 3 yellow marbles have to remain in bag, and there are already 3 yellows so we dont have to calculate or add any yellow marble? As i can see the solution for only blue marbles


We have 3 yellow and 5 blue marbles.
After 2 marbles are randomly removed, what is P(3 yellow and 3 blue marbles remain)?
In order for yellow and 3 blue marbles to REMAIN, we must REMOVE 2 blue marbles.

So, P(3 yellow and 3 blue marbles REMAIN) = P(2 blue marbles are REMOVED)

Does that help?
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Re: A bag contains 3 yellow and 5 blue equally sized marbles. Tw [#permalink]
GreenlightTestPrep wrote:
Farina wrote:
I dont understand the solution sorry :(
It says 3 yellow marbles have to remain in bag, and there are already 3 yellows so we dont have to calculate or add any yellow marble? As i can see the solution for only blue marbles


We have 3 yellow and 5 blue marbles.
After 2 marbles are randomly removed, what is P(3 yellow and 3 blue marbles remain)?
In order for yellow and 3 blue marbles to REMAIN, we must REMOVE 2 blue marbles.

So, P(3 yellow and 3 blue marbles REMAIN) = P(2 blue marbles are REMOVED)

Does that help?


So we have to find probability of those which are going to be removed. Therefore (un)favorable/total = 5/8 * 4/7
I hope I understood it correctly
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Re: A bag contains 3 yellow and 5 blue equally sized marbles. Tw [#permalink]
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Farina wrote:
So we have to find probability of those which are going to be removed. Therefore (un)favorable/total = 5/8 * 4/7
I hope I understood it correctly


That's correct.
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Re: A bag contains 3 yellow and 5 blue equally sized marbles. Tw [#permalink]
GreenlightTestPrep wrote:
Farina wrote:
So we have to find probability of those which are going to be removed. Therefore (un)favorable/total = 5/8 * 4/7
I hope I understood it correctly


That's correct.


Thanks. Just one confusion, we have to find probability of those that remain in bad so wont we subtract the probability the ones which we have removed? Only then we can find the probability of those remaining in bag
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Re: A bag contains 3 yellow and 5 blue equally sized marbles. Tw [#permalink]
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