A committee of 7 has to be formed from 8 boys and 4 girls. In how many ways can this be done when the committee consists of: i) atleast 3 girls.      Ii) atmost 2 girls ​

1. total no of members needed =7
   no. of boys =8
  no. of girls =4
if at least 3 girls should be selected then - these cases are possible :-
a). 3 girls and 4 boys must be in the committee 
b). 4 girls and 3 boys must be in the committee
then , total possible permutations = ( 4p_{3 *} 8p₄ ) + ( ^4p₄ * ^8p₃ ) 

2. if  atmost 3 girls should be selected then - these cases are possible :-
a). 1 girl and 6 boys
b). 2 girls and 5 boys
then , total possible permutations =  ( 4p₁ * ^8p₆ ) + ( ^4p₂ * ^8p₅ )

I HOPE THIS WILL BE HELPFUL. 
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