What is the probability of drawing a pink ball from a box?

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Source: — Data Sufficiency |

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by shiraj » Wed May 28, 2008 1:20 am
Answer: D

(1) Since there is no pink ball, so the probability of drawing a pink ball is zero.

(2) The probability of drawing a pink ball is 6/20 => 3/10

Hence, answer is D

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by mim3 » Wed May 28, 2008 10:07 am
shiraj wrote:Answer: D

(1) Since there is no pink ball, so the probability of drawing a pink ball is zero.

(2) The probability of drawing a pink ball is 6/20 => 3/10

Hence, answer is D
Where is this question from? The question leaves a lot for assumption or the statements contradict each other, which never happens. In either case, it seems weird.

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by chidcguy » Wed May 28, 2008 10:15 am
shiraj wrote:Answer: D

(1) Since there is no pink ball, so the probability of drawing a pink ball is zero.

(2) The probability of drawing a pink ball is 6/20 => 3/10

Hence, answer is D
Wow! If there is no pink ball, we can't find the probability because we can't pick it. More over it does not say that Pink balls are not there (or) only red and black balls are there Also, it does not tell the total number of balls of all type. . IMO, Insuffcient

I agree with the 2nd above and answer is B. Of course one has to assume that 6 out of 20 meant 20 is the total number of balls

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by netigen » Wed May 28, 2008 10:37 am
It does seem weird.

This question is from crack-gmat free test

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by amitansu » Fri May 30, 2008 3:06 am
A wise guess would be : from step 2 we know that there are some pink balls at least.

So 1 is in sufficient.

2 is sufficient for th obvioue reason.

So 'B' would be ans here.