gmat prep question
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A certain office supply store stocks 2 sizes of self stick notepads, each in 4 colors: blue, green, yellow and pink. the store packs the notepads in packages that contain either 3 notepads of the same size and the same color or 3 notepads of the same size and of 3 different colors. I fthe order, in which the colors are packed is not consumed, how many different packages of the types described above are possible?
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We have to compute the numbers over 2 cases --yvonne12 wrote:A certain office supply store stocks 2 sizes of self stick notepads, each in 4 colors: blue, green, yellow and pink. the store packs the notepads in packages that contain either 3 notepads of the same size and the same color or 3 notepads of the same size and of 3 different colors. I fthe order, in which the colors are packed is not consumed, how many different packages of the types described above are possible?
1 - Same size, same color
2C1 * 4C1 = 8
2 - Same size, 3 unique colors
2C1 * 4C3 = 8
Hence total = 16
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- jayhawk2001
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I found quite a bit of resources on Beat the GMAT Math wiki thatyvonne12 wrote:yes 16 is the answer,
jayhawk, can you tell me where I can go to extend my knowledge on combinatrics, its seems to be a weakness of mine.
was exclusively probability and combination. That might be a good
start. After that, practice practice practice and you'll see some common
themes.
I wish I could suggest a book but unfortunately I haven't seen one
that deals exclusively with GMAT type probability questions.