问一道 prep 数学题

qx02

if k is an  integer and 2 <k<8 ,what is the value of k ?

1 k is a factor of 30

2 k si a factor of 12

我觉得 应选b, 12 = 2*2*3  

2<3<8.

为什么 答案是 e ?

 

题意什么意思？ 看不懂。and what is the solution?   

[此贴子已经被作者于2008-10-13 7:54:07编辑过]

ccergsm

factors of 30 include 1 2 3 5 6 10 15 30. factors of 12 include 1 2 3 4 6 12