GMAT一道数学题Whatis型提问要唯一解么?Whatistheremainderwhenthepositiveintegernisdividedbythepositiveintegerk,wherek>(1)n=(k+1)3(2)k=5Statement(1)ALONEissufficient,butstatement(2)aloneisnotsufficient.St

Question

GMAT一道数学题 What is型提问要唯一解么?
What is the remainder when the positive integer n is divided by the positive integer k,where k >
(1) n = (k+1)3
(2) k = 5
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.
为什么

Answer 1

题目：求余数,当正整数n除以正整数k,且k>1.
条件1:n=(k+1)^3 【我不确定你这里是三次方还是括号乘以3,不过我估计是三次方】
条件2:k=5
既然你说答案是A了,即条件1单独成立,那么这里就直接看条件2好了.
条件2即是当仅知道k=5的时候,不知道n的具体数值时,余数无法确定.
回头看条件1,当n=(k+1)^3,结合题目已知条件k>1,用最简单的代入法,可知:
k=2时,n=(2+1)^3=27,此时余数为27/2=13+1; k=3时,n=(3+1)^3=64,此时余数为64/3=21+1.
我这里就不列举了.仅仅列举两个便可发现此时余数无论如何都是固定的,为1.
因此当条件1单独成立时,此题选A.