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by shibal » Tue Jun 30, 2009 6:24 pm
there are 2 sizes of post its. Each has 4 colors – Blue, Green, Yellow, and Purple. The pads are packed in packages that contain either 3 notepads of same size and same color or 3 notepads of same size and of 3 different colors. How many different packages of the types described are possible?

i get 8 oa 16
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by tohellandback » Tue Jun 30, 2009 9:35 pm
if boxes are A and B with 4 colors each
3 notepads of same size and same color: box A and any of the colors-4 ways
or box B and any of the 4 colors- 4 ways

3 notepads of same size and of 3 different colors:

box A and 3 out of 4 colors-4 ways
or box B and 3 out of 4 colors-4 ways
total =4+4+4+4 =16 ways
The powers of two are bloody impolite!!
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by shanmugam.d » Wed Jul 01, 2009 7:30 am
The other approach is:
notepads of same size and same color = 2 x 4 =8
(2 size times 4 colours)

notepads of same size and of 3 different colors = 2 x 4P3 = 8
(permutation of 3 diferent colors from 4 colors times 2 different sizes)

total combination = 8+8 = 16
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by shibal » Wed Jul 01, 2009 3:53 pm
omg... of course, I forget about the 2 different sizes....
thanks guys..
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