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प्रश्न
A bag contains six white marbles and five red marbles. Find the number of ways in which four marbles can be drawn from the bag if two must be white and two red
उत्तर
Total number of marbles = 6 white + 5 red = 11 marbles
If 2 must be white and 2 must be red
Then the required number of ways = 6C2 × 5C2
Hence the required number of ways are 6C2 × 5C2
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