GmatPrep (comb/prob)

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by AleksandrM » Sun Jun 01, 2008 3:05 pm
I got 32.

4!/3!(4 - 3)! * 4!/3!(4 - 3)! * 2

4 * 4 * 2 = 32.

More of a stab in the dark than anything else.

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by 2008nv » Sun Jun 01, 2008 4:56 pm
The answer is C...

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by jasonc » Sun Jun 01, 2008 5:05 pm
1C2*3C4 = 2*4 = 8 (1 size from 2, 3 colors from 4)
1C2*1C4 = 2*4 = 8 (1 size from 2, 1 color from 4)

8+8=16
I beat the GMAT! 760 (Q49/V44)

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by ksh » Mon Jun 02, 2008 8:16 am
Hi 2008nv,

here the order is not considered so it will be a combination

2 sizes, 4 c0lors.
First case- same size, same color it means
Total ways =2C1*4C1=2*4=8

second case- same size, 3 different colors
total ways= 2C1*4C3=2*4=8

therefore, total ways=8+8=16
Answer C