jelly beans

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jelly beans

by preetha_85 » Mon Aug 04, 2008 10:35 am
Hi

Bowls X and Y each contained exactly 2 jelly beans, each of which was either red or black. One of the jelly beans in bowl X was exchanged with one of the jelly beans in bowl Y. After the exchange, were both of the jelly beans in bowl X black?
(1) Before the exchange, bowl X contained 2 black jelly beans.
(2) After the exchange, bowl Y contained 1 jelly bean of each color.

OA is E

But i get C can some body explain.. thanks
Last edited by preetha_85 on Mon Aug 04, 2008 10:20 pm, edited 1 time in total.
Source: — Data Sufficiency |

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by bha » Mon Aug 04, 2008 10:44 am
What is the OA?

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by parallel_chase » Mon Aug 04, 2008 11:19 am
X contains 2 jelly beans, Y contains 2 jelly beans.

each of these 2 jelly beans can be black or red

x can have 2 red or 2 black or 1 red and 1 black

1 jelly bean is exchanged between x and y, it can be red or black

Statement I
Before the exchange, bowl X contained 2 black jelly beans.
we dont know anything about y, therefore insufficient.

Statement II
After the exchange, bowl Y contained 1 jelly bean of each color.
we dont know anything about x, therefore insufficient.

Combing I & II
Even after combining we dont know if Y had Black or Red Jelly beans before the exchange.

If y had 2 red jelly beans before the exchange then x would have 1 red and 1 black after the exchange.

If y had 1 red and 1 black jelly bean before the exchange then x can either have 2 black or 1 red and 1 black after exchange.

Hence Insufficient. The answer is E.

Hope this helps.

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by preetha_85 » Mon Aug 04, 2008 10:19 pm
Thanks.. parallel_chase.

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by 2010gmat » Wed Apr 01, 2009 9:24 am
parallel_chase wrote:X contains 2 jelly beans, Y contains 2 jelly beans.

each of these 2 jelly beans can be black or red

x can have 2 red or 2 black or 1 red and 1 black

1 jelly bean is exchanged between x and y, it can be red or black

Statement I
Before the exchange, bowl X contained 2 black jelly beans.
we dont know anything about y, therefore insufficient.

Statement II
After the exchange, bowl Y contained 1 jelly bean of each color.
we dont know anything about x, therefore insufficient.

Combing I & II
Even after combining we dont know if Y had Black or Red Jelly beans before the exchange.

If y had 2 red jelly beans before the exchange then x would have 1 red and 1 black after the exchange.

If y had 1 red and 1 black jelly bean before the exchange then x can either have 2 black or 1 red and 1 black after exchange.

Hence Insufficient. The answer is E.

Hope this helps.
. Bowls X and Y each contained exactly 2 jelly beans, each of which was either red or black. One of the jelly beans in bowl X was exchanged with one of the jelly beans in bowl Y. After the exchange, were both of the jelly beans in bowl X black?

I am getting the answer as B...

I agree with your approach only till statement I, but i interprate the bold statement as follows ..and statement 2 gives us

Since each ball is either Red or Black (correct me if i am wrong )

Bowl X can have 2 black balls or 2 red balls and same goes for Bowl Y...they cannot have 1 red and 1 black sort of combo ...

Now since Y has 2 different jellies ultimately .. this means X and Y didn't had same colored jellies initially...we can have following combos

X - 2 BLACK AND Y - 2 RED OR
X - 2 RED AND Y - 2 BLACK ..

but in either case we will not have 2 black jellies in X...which can be definitely answered using statement 2.

Hence Answer B...

I know answer is given as E...

Need help :shock: