If d is a positive integer and f is the product of the first 30 positive integers, what is the value of d ?
(1) 10d is a factor of f.
(2) d > 6
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
30!可以拆分出7个10作为因子,这是因为:5,10,15,20,25,30都是30!的因子,其中25可以变成5*5,所以包含两个可变为10的因子5(10本身是因子,5可以和任意偶数相乘变因子)
那么条件1:d可以是小于等于7的任意正整数。NS
条件2:由于不知道f和d的关系所以不足以求出d。NS
1+2:这时限定了d只能等于7。S
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