stubbornp wrote:18. 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.
X = 1 red, 1 black or both red or both black.
Y = 1 red, 1 black or both red or both black.
Statement I
Before the exchange, bowl X contained 2 black jelly beans.
Y = 1 red, 1 black or both red or both black.
After the exchange,
X can have both black, if Y had both black before the exchange,
X can have both black, if Y had 1 red and 1 black before the exchange and black exchanged with black.
X can have 1 red and 1 black, if Y had 1 red and 1 black before the exchange and black exchanged with red.
X can have 1 red and 1 black, if Y had both red.
Insufficient.
Statement II
After the exchange, bowl Y contained 1 jelly bean of each color.
we can again have several cases as mentioned above.
Insufficient.
Combining I & II
Before,
X= both black
After,
Y = 1 red + 1 black
There can be 2 cases
Before exchange Y = both red
After exchange,
X = 1 red and 1 black, Y = 1 red and 1 black, and red in Y got exchanged with black in X.
Before exchange Y = 1 red + 1 black
After exchange,
X = both black, Y = 1 red + 1 black, and black in Y got exchanged with black in X.
Insufficient.
Hence E.
OA?
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