请教两道没看懂题目要求的GWD~~

xyqirene

If each of the 12 teams participating in a certain tournament plays exactly one game with each of the other teams, how many games will be played?



A.144
B.132
C.66
D.33
E.23

答案 c


A school administrator will assign each student in a group of n students to one of m classrooms.If 3 < m < 13 < n, is it possible to assign each of the n students to one of the m classrooms so that each classroom has the same number of students assigned to it?

(1)It is possible to assign each of 3n students to one of m classrooms so that each classroom has the same number of students assigned to it.

(2)It is possible to assign each of 13n students to one of m classrooms so that each classroom has the same number of students assigned to it.



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.
Answer: B



A school administrator will assign each student in a group of n students to one of m classrooms.If 3 < m < 13 < n, is it possible to assign each of the n students to one of the m classrooms so that each classroom has the same number of students assigned to it?

(1)It is possible to assign each of 3n students to one of m classrooms so that each classroom has the same number of students assigned to it.

(2)It is possible to assign each of 13n students to one of m classrooms so that each classroom has the same number of students assigned to it.



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.
Answer: B

maximeason

我来解答
第一题 以每一个队伍来考虑 一个队伍必然要打11场球
这样12*11
然后你会发现会有重复 比如A和B打算一场的话 在计算B的时候 B于A打也计算在内
所以要除以2~~~~

maximeason

第二题 题目很罗嗦 其实就是说 N是否可以被M整除
1 3n可以被M整除 好比说n为16 3n为48  48的因子有许多 比如说 我们拿6出来 设m为六 那么16是不能被6整除的
213n  13*n/m 是可以除尽的 因为3<m<13 所以 13/m是无法除尽的
只能是n/m可以除尽

这个题的思路在于找到m的取值范围 和之后3,13的关系 挺微妙的

xyqirene

恩···谢谢了·  第二题总算明白····  当时看题就用了好久···  想想如果在考场 就只有乱蒙一个了····悲剧~~~