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.
条件一:10的D次方是30!的一个因子; 30!含有多个10,10=2*5,2的数量比较多,主要决定在5的个数,含有5的数字:5,10,15,20,25,30,6个数字里含有7个5,那么D的上限是7, 不能推出具体的D,不充分了
条件二: D>6,也是个范围,不充分
1+2,得出d=7,充分
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