Answer:
4.44
Explanation:
Total NM of ball=18,
black ball=4
p(black,black)=?
p(black,black)=p(b)+p(b)
4/18+4/18=4.44ans
Total number of marbles:
Probability of black marble:
Without replacement, we have 3 black out of 17 total, then probability of the second black is:
Required probability is:
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