Question
Mathematics Question on permutations and combinations
There are 4 men and 5 women in Group A, and 5 men and 4 women in Group B. If 4 persons are selected from each group, then the number of ways of selecting 4 men and 4 women is
Answer
We need to select 4 men (M) and 4 women (W) from the two groups. Consider the following cases:
From Group A | From Group B | Ways of Selection |
---|---|---|
4M | 4W | (44)⋅(44)=1 |
3M1W | 1M3W | (34)⋅(15)⋅(35)⋅(14)=400 |
2M2W | 2M2W | (24)⋅(25)⋅(25)⋅(24)=3600 |
1M3W | 3M1W | (14)⋅(35)⋅(15)⋅(34)=1600 |
4W | 4M | (45)⋅(45)=25 |
Total | 5626 |
Final Answer: 5626.