A) 11
B) 9
C) 12
D) 7
Correct Answer: C
Solution :
There are m men and 2 women. So, number of games played by the men between themselves \[{{=}^{m}}{{C}_{2}}\times 2\] And number of games played between men and women \[{{=}^{m}}{{C}_{1}}^{2}{{C}_{1}}\times 2\] \[\therefore \]\[^{m}{{C}_{2}}\times 2{{=}^{m}}{{C}_{1}}^{2}{{C}_{1}}\times 2+84\] \[\Rightarrow \]\[m(m-1)=m\times 2\times 2+84\] \[\Rightarrow \]\[{{m}^{2}}-5m-84=0\]\[\Rightarrow \]\[(m-12)(m+7)=0\] \[\Rightarrow \]\[m=12\]or \[-7\] \[\because \] m cant be negative, so m = 12.
You need to login to perform this action.
You will be redirected in
3 sec
