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In a box, there are 5 black pens, 3 white pens and 4 red pens. In how many ways can 2 black pens, 2 white pens and 2 red pens can be chosen?

Correct Answer: 180

Explanation:

Number of ways of choosing 2 black pens from 5 black pens in 5 C 2  ways.


 


Number of ways of choosing 2 white pens from 3 white pens in  3 C 2  ways.


 


Number of ways of choosing 2 red pens from 4 red pens in 4 C 2 ways.


 


By the Counting Principle, 2 black pens, 2 white pens, and 2 red pens can be chosen in 10 x 3 x 6 =180 ways.


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