作者DanceDan (Dan)
看板GMAT
標題[解題]看不懂的考古題
時間Sun Apr 6 16:40:52 2008
each of the integers from 0 to 9,inclusive, is written on a separate slip of
blank paper and the ten slips are dropped into a hat.If the slips are then
drawn one at a time without replacement,how many must be drawn to ensure that
the numbers on two of the slips drawn will have a sum of ten?
a.3
b.4
c.5
d.6
e.7
答案是e~
我看了好多遍都看不懂～
可以請厲害的版友們幫我解題嗎？
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1F：推 kelpiejo:0 1 2 3 4 5 6 最多要7次才有辦法湊到兩個和為10 04/06 16:45
2F：推 Rock21:還是不懂0.0 04/06 17:21