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Question
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 they must all be of the same colour.
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Solution
Total number of marbles = 6 white + 5 red = 11 marbles
If all the 4 marbles are of the same colour
Then, the required number of ways = 6C4 + 5C4
Hence the required number of ways are 6C4 + 5C4.
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