one pick up to get 9

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one pick up to get 9

by sanju09 » Tue Feb 23, 2010 3:26 am
A box contains 20 balls, of which 4 are white, 7 are black and 9 are red. At least how many balls must one pick up to get 9 balls of the same color?
(A) 16
(B) 17
(C) 18
(D) 19
(E) 20
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by ajith » Tue Feb 23, 2010 3:38 am
sanju09 wrote:A box contains 20 balls, of which 4 are white, 7 are black and 9 are red. At least how many balls must one pick up to get 9 balls of the same color?
(A) 16
(B) 17
(C) 18
(D) 19
(E) 20
The only possibility of getting 9 balls of the same color is to pick all the reds. Because of sheer luck, one might get the last red ball in the last pick so, to be sure, one should pick all 20.
Always borrow money from a pessimist, he doesn't expect to be paid back.

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by harsh.champ » Tue Feb 23, 2010 3:59 am
sanju09 wrote:A box contains 20 balls, of which 4 are white, 7 are black and 9 are red. At least how many balls must one pick up to get 9 balls of the same color?
(A) 16
(B) 17
(C) 18
(D) 19
(E) 20
20 E would be the answer
If it was 4white,11 black , 9 red ,then would have been a lil bit tough.
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by firdaus117 » Tue Feb 23, 2010 5:10 am
harsh.champ wrote: If it was 4white,11 black , 9 red ,then would have been a lil bit tough.
Not really,in that case answer will be 21 if you are not talking about exact 9 balls.

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by harsh.champ » Tue Feb 23, 2010 6:19 am
firdaus117 wrote:
harsh.champ wrote: If it was 4white,11 black , 9 red ,then would have been a lil bit tough.
Not really,in that case answer will be 21 if you are not talking about exact 9 balls.
Okk!! B-) Difficulty level varies for diff. people across diff. sections :!:
It seemed difficult for me that way. :cry:
Anyways good for u that u find such problems easy
Definitely gng 2 score big in the quant,eh?? :lol:
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Just because something is hard doesn't mean you shouldn't try,it means you should just try harder.

"Keep Walking" - Johnny Walker :P