Eight persons in an organization including X and Y were to be divided in two groups of 4 members each. The total number of groups containing both X and Y is what fraction of the total number of groups which can be formed? Choose the correct choice from the following answers
A) 1/4
B) 3/14
C) 4/14
D) 1/10
E) 11/14
The fraction is nothing but the probability..   Number to choose 4 out of 8= 8C4..   Number to choose X and Y and 2 from remaining 6=6C2..   prob of X and Y choosen=6C2/8C4= {6!/4!2!}/{8!/4!4!}..   6!4!4!/8!4!2!=3/2*7=3/14   Answer : 3/14
<result>B</result>
Eight persons in an organization including X and Y were to be divided in two groups of 4 members each. The total number of groups containing both X and Y is what fraction of the total number of groups which can be formed?