PP-T1-DS38

[max999]

If r and s are positive integers, is r/s an integer?

(1) Every factor of s is also a factor of r.
(2) Every prime factor of s is also a prime factor of r.

answer:A


想請問 (2) 爲啥不行
還有幫我舉各prime factor 的例子, 不太了解 Thanks

[Huang Hsin-Yi]

(2) 2,3,25/2,3,8