# Probability A bag contains 6 red balls and 9 black balls. two draws are made

A bag contains 6 red balls and 9 black balls. two draws are made. find the probability that the first draw will give 4 red and second draw will give 3 black balls. when 1) balls are replaced after the first draw 2) balls are not replaced

I tried this

By Replacing balls

1) 15C4

2) 15C3

By non Replacement

1) 15C4

2) 11C3

Is this correct?

Or

By Replacing balls

1) 4/15

2) 3/15 = 1/5

By non Replacement

1) 4/15

2) 3/11

Is this correct?

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How many balls are drawn on the first draw? Second draw? Is it $4$ and $3$ respectively? –  André Nicolas Jan 5 '13 at 5:35
And there are a couple of interpretations of "with replacement." We could draw a total of say $4$ on the first draw, one at a time, replacing each time, or remove them all at once, replacing only when it is time for the second draw. If this is homework, I assume the question must be more explicit than what you have written. –  André Nicolas Jan 5 '13 at 5:52