菜鸟求解一数学题

deenlay22

题目是：  If n is an integer （整数）and 2 < n < 6, what is the value of n?(1)      n is a factor of 15.(2)      n is a factor of 21.    A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.D. EACH statement ALONE is sufficient.E. Statements (1) and (2) TOGETHER are NOT sufficient.为什么选 B

deenlay22

知道了,好简单,一下子懵了

幻世弋无双

（1）n是15的因数，那就是3和5其中之一，在 2 < n < 6无法确定其值
（2）n是21的因数，那就是3和7其中之一， 2 < n < 6中确定为3

因此选B

楼主你首先要明白那些选项的意思