thanhtam269 wrote:

(1) definitely not sufficient alone, cause we need to know how many men and women (not how many total of men and women).

(2) is also not sufficient. Let's assume that x and y both larger than or equal to 3, so the number of committees that can be formed is (3Cx * 1Cy) + (1Cx * 3Cy)

Clearly if we swap x and y this sum is not changed, so (2) is always right for x, y >= 3

Combine (1) and (2) we see that (x, y) can be (3, 9), (4, 8), (5, 7) or (6, 6), hence we still can't calculate the result.

=> The answer is E

Hi Thanhtam, thanks for the explanation. I would like to ensure I am thinking about this correct

Case 1:

(3, 9), will result in one committee and will give the same exact value when reversed as modeled by your equation.

Case 2:

(6,6) will result in two committees and will give the exact same value when reversed as modeled.

My confusion comes in the equation you've written. I wanted to do this

W=3 M =9

3W:1M Only one group can be formed

3M:1W Three groups can be formed.

Total groups for case 1(Men =x and women =y) \(3+1=4\)

M=9 W=3

3W:1M Only one group can be formed

3M:1W Three groups can be formed

Total groups for case 2(Men = y and women = x ) \(3+1=4\)

Thus overall total groups = 8

In the case of 1W & 11M

3W:1M 0 group can be formed

1W:3m 1 group can be formed

Total groups from case 1: = 1

Case 2: 11W 1M

3W:1M = 1 group can be formed

3M: 1W = 0 groups can be formed

Total groups for this case = 2.

Therefore there are 2 different cases, one in which total groups = 8, and one in which total groups = 2

I know my method will take too long for the Gmat time constraint, can you explain to me how exactly you came to derive your equation?

Thanks in advance