Statisticshard · Past Paper
An urn contains 4 red, 5 blue and 6 green balls. Three balls are drawn at random. What is the probability that all are of different colors?
A4/91
B24/91
C1/455
D12/455
✓ Correct Answer: B — 24/91
Ways to pick 1 of each = 4*5*6 = 120. Total ways = 15C3 = (15*14*13)/(3*2*1) = 455. 120/455 = 24/91.
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