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If I draw 2 balls from a bag which contains 2 pink, 3 blue and 4 orange balls, what's the probability that the first ball would be pink and the second blue - as a decimal? Thanks. :)

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    Hi. Assuming the first one is pink. Need the probability that both, the first one would be pink and the second blue. :) Thanks.2012-07-03

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Hint: what is the chance that you get a pink ball on the first draw? Given that one pink ball is removed (I presume you are drawing without replacement), what is the chance that the second draw is blue? The chance of both is the product. Now you have a fraction to express in decimal. What fraction is it?

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    Ah, I see. Thanks again Ross. :)2012-07-03
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The probability to pick up the first ball pink is $\frac{2}{9}$ that means 0.22. If you don't get the first ball blue, the probability to have the second ball blue is $\frac{3}{8}$ ($0.375$). If the first ball is blue, the probability to have the secon ball of the same colour is: $\frac{1}{4}$ ($0.25$). The probability to pick the first pink and the second blue is in the first case: $\frac{2}{9}\frac{3}{8}$, in the second: $\frac{2}{9}\frac{1}{4}$