# Math Help - Help Please

A 4-person grievance committee is to be composed of employees in 2 departments, A and B, with 15 and 20 employees respectively. If the 4 people are selected at random from the 35 employees, what is the probability of selecting:
1) 3 from A and 1 from B
2) 2 from A and 2 from B
3) All from A
4) At least 3 from A

2. The following gives the probability in terms of the number from A.
$P(A = k) = \frac{{\left( {\begin{array}{*{20}c}
{15} \\
k \\

\end{array} } \right)\left( {\begin{array}{*{20}c}
{20} \\
{4 - k} \\

\end{array} } \right)}}
{{\left( {\begin{array}{*{20}c}
{35} \\
4 \\

\end{array} } \right)}},\;\;k = 0,1, \cdots 4$

To answer the first one, let k=3.