作者catspace (柏拉图的永恒...)
看板GMAT
标题Re: [计量] PP1的PS
时间Sat Jan 3 17:08:38 2009
※ 引述《gwuho (JOe)》之铭言：
: A certain office supply store stocks 2 sizes of self-stick notepads,
: each in 4 colors: blue, green, yellow, or pink.
: The stock 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. If the order in which the colors are packed is not considered,
: how many different packages of the types described above are possible?
: Ans:16
: 请问思路要怎麽走? thx~
两种选择方式
(1)同尺寸同颜色
尺寸2选1 * 颜色4选1 = 2*4 = 8种
(2)同尺寸不同颜色
尺寸2选1 * 颜色4种任选3 = 2 * C4取3 = 8种
加起来16种 #
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