Answer
20 groups
Work Step by Step
The order of the chosen employees does not matter.
Combinations: ${}_{n}C_{r}=\displaystyle \frac{n!}{(n-r)!r!}$
${}_{6}C_{3}=\displaystyle \frac{6!}{(6-3)!3!}=\frac{6\times 5\times 4}{1\times 2\times 3}=20$
