A committee of 7 has to be formed from 9 boys and 4 girls. In how many ways can this be done when the committee consists of
(i) Exactly 3 girls
(ii) At least 3 girls
(iii) At most 3 girls
(i) A committee consisting of 3 girls and 4 boys can be formed in
ways
=504 ways
(ii) A committee having at least 3 girls will consists of
(a) 3 girls 4 boys
(b) 4 girls 3 boys
This can be done in
ways
(iii) A committee having at most 3 girls will consist of
a) No girl 7 boys
b) 1 girl, 6 boys
c) 2 girls, 5 boys
d) 3 girls, 4 boys
