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On the occasion of Dipawali festival eac...

On the occasion of Dipawali festival each student of a class sends greeting cards to others. If there are 20 students in the class, the number of cards sends by students is

A

`""^(20)C_(2)`

B

`""^(20)P_(2)`

C

`2xx""^(20)C_(2)`

D

`2xx""^(20)P_(2)`

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The correct Answer is:
A, B, C
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CHHAYA PUBLICATION-MISCELLANEOUS EXAMPLES-WBJEE 2018
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