Question 374877
nCr=Combination of n things taken r at a time=n!/((n-r)!r!)
(300C7 * 699C3)/999C10 = .0088 = 88/10,000 Probability that 7 of those numbers will be from 700 to 999.
10000-88=9912
Odds against 7 of those numbers will be from 700 to 999 = 9912 to 88 or 113 to one. The odds in favor are the reverse, one to 113.
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Ed