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On the occasion if Deepawali festival, e...

On the occasion if Deepawali festival, each student in a class sends greeting cards to other. If there are 20 students in the class, find the total number of greeting cards exchanged by the students?

Text Solution

Verified by Experts

The correct Answer is:
`2 .^(20)C_(2)`
Number of cards exchanged is `2xx` (number of ways 2 students can be selected who will exchange cards), which is given by `2 .^(20)C_(2)`.
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