求教一道数学题

yunshishow

If N, C, and D are positive integers, what is the remainder when D is divided by C?

1   If D+1 is divided by C+1, the remainder is 5.
2  If ND+NC is divided by CN, the remainder is 5.

    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)     Statement (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data are needed.

lizzieonline

mark

czghy

貌似是Ｂ，对吗？

yunshishow

是的哈，怎么解呢？一直想不明白此题。

pinkowen10

B吧。。
条件一：D+1=K(C+1)+5 推出 D=KC+4+K 余数为4+K 不充分
条件二：(ND+NC)/CN=K+5 推出 D/C=K+4 余数为四 充分

yunshishow

明白了，谢谢解答哈~~~