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samirpatadia
- Newbie | Next Rank: 10 Posts
- Posts: 3
- Joined: Fri Apr 09, 2010 10:45 am
Q1. A group of 8 friends want to play doubles tennis. How many different ways can the group be divided into 4 teams of 2 people.
A. 420
B. 2520
C. 168
D. 90
E. 105
Q2. In how many different ways can a group of 9 people be divided into 3 groups, with each group containing 3 people?
A. 252
B. 1260
C. 1680
D. 2520
E. 3360
The ans for Q1 is E. and for Q2 its C.
My question is in Q1 we divide the expression 8c2 * 6c2 * 4c2 * 2c2 by 4!
However, in Q2 we do not divide expression 9c3 * 6c3 * 3c3 by 3!
Can anyone explain me whats the fundamental difference between Q1 and Q2.
Thanks in Advance
A. 420
B. 2520
C. 168
D. 90
E. 105
Q2. In how many different ways can a group of 9 people be divided into 3 groups, with each group containing 3 people?
A. 252
B. 1260
C. 1680
D. 2520
E. 3360
The ans for Q1 is E. and for Q2 its C.
My question is in Q1 we divide the expression 8c2 * 6c2 * 4c2 * 2c2 by 4!
However, in Q2 we do not divide expression 9c3 * 6c3 * 3c3 by 3!
Can anyone explain me whats the fundamental difference between Q1 and Q2.
Thanks in Advance
