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Question
Three balls are drawn from a bag containing 5 red, 4 white and 3 black balls. The number of ways in which this can be done if at least 2 are red is ______.
Solution
Three balls are drawn from a bag containing 5 red, 4 white and 3 black balls. The number of ways in which this can be done if at least 2 are red is 80.
Explanation:
We have 5 red, 4 white and 3 black balls out of which atleast 2 red balls are to be drawn
∴ Number of ways = 5C2 × 7C1 + 5C3
= 10 × 7 + 10
= 70 + 10
= 80
Hence, the value of the filler = 80.
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