A man X has 7 friends, 4 of them are ladies and 3 are men. His wife Y also has 7 friends, 3 of them are ladies and 4 are men. Assume X and Y have no common friends. Then the total number of ways in which X and Y together can throw a party inviting 3 ladies and 3 men, so that 3 friends of each of X and Y are in this party, is :
468
469
484
485
As we learnt in
Theorem of Combination -
Each of the different groups or selection which can be made by taking r things from n things is called a combination.
- wherein
Where
We use combinations
Total number f ways
Correct option is 4.
Option 1)
468
This is an incorrect option.
Option 2)
469
This is an incorrect option.
Option 3)
484
This is an incorrect option.
Option 4)
485
This is the correct option.
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