Question 1092067
<br>The total number of ways of forming a committee of 4 from 12 students is "12 choose 4", which is
{{{C(12,4) = (12!)/((8!)(4!)) = 495}}}<br>
The number of ways of forming the committee with only boys is "9 choose 4",
{{{C(9,4) = (9!)/((5!)(4!)) = 126}}}<br>
So the number of ways of forming the committee with at least one girl is 495-126=369.