Answer:

Explanation:
GIVEN: A committee of eight congressman will be selected from a group of
Democrats and
Republicans.
TO FIND: The number of ways of obtaining a committee with exactly
Democrats.
SOLUTION:
Total number of congressman in committee

Total number of republicans available

Total number of democrats available

As, the committee should have exactly
democrats, there will be
republicans in committee
No. of ways of selecting
democrats out of
democrats


NO. of ways of selecting
republicans out of
republicans



The number of ways of obtaining a committee with exactly
Democrats.



Hence there are
ways to form a committee in which there are exactly
democrats.