Statisticshard · Past Paper
In a box, there are 10 red, 20 blue and 30 green marbles. 5 marbles are drawn. What is the probability that all are blue?
A20C5 / 60C5
B20 / 60
C1/5
D1/12
✓ Correct Answer: A — 20C5 / 60C5
Probability = (Number of ways to choose 5 blue) / (Total ways to choose 5) = 20C5 / 60C5.
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