Q. 64.8( 5 Votes )

# How many committee of five persons with a chairperson can be selected from 12 persons. [Hint: Chairman can be selected in 12 ways and remaining in ^{11} C_{4}.]

Answer :

Formula:- (i)^{n}C_{r}

A chairperson can be selected in =12

The 4 other person can be selected by

=^{11}C_{4}

Selection of 5 people can be done in

=330 x 12

=3960

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