gwd-28-34/28-37

cournot

34:The operation Θ is defined by x Θ y =  1/x+1/y  for all nonzero numbers x and y.  If z is a number greater than 1, which of the following must be true?

 I.  x Θ (-z) = 0

             II.  z Θ  = 1

            III.   Θ  = z

A.          I only

B.          I and II only

C.          I and III only

D.          II and III only

E.          I, II, and III

为I也成立，我选D,答案为何为E

Q37:In a meeting of 3 representatives from each of 6 different companies, each person shook hands with every person not from his or her own company.  If the representatives did not shake hands with people from their own company, how many handshakes took place?

A.      45

B.      135

C.      144

D.     270

E.      288

这个题目数字是不是有问题，大家帮我看看，答案为b

lovetiky

Q37 ：

如果18个人都两两握一次手，不管是不是同一个公司，那么将会握C(18 2)=153次

同一个公司的三个人握C(3 2)=3次，六个公司一共6*C(3 2)=18次

所以最终153-18=135次

 

Q34没看懂~

[此贴子已经被作者于2006-6-3 11:03:46编辑过]

tikyluo

以下是引用cournot在2006-6-3 5:53:00的发言：

Q34:The operation Θ is defined by x Θ y =  +
             for all nonzero numbers x and y.  If z is a number greater than 1, which of the following must be true?

 I.  x Θ (-z) = 0

             II.  z Θ  = 1

            III.   Θ  = z

A.          I only
                    

B.          I and II only

C.          I and III only
                    

D.          II and III only
                        

E.          I, II, and III

为I也成立，我选D,答案为何为E

 lz的
                x Θ y =  +  是不是写错了,或者漏了一些东西呢? 确实看不懂~~

cournot

Q37 a meeting of 3 representatives from each of 6 different companies我理解成一共只有3个人，来此6个不同的公司，没有好好理解each；

Q34题目改正了

yaoyao99

I think I is a typo.  It should be z Θ (-z).

Please rename your subject so others can find answer quickly.  The format  is GWD-AA-BB                                                   (AA表示套数,BB表示题数).  Thank you for understanding!

cournot

thanks,滔滔31套的看来有些type有些错误

标题gwd-28-34,37可以么，28表示套数，34,37表示题数

yaoyao99

Best if you could post the questions separately.  If someone is searching for gwd-28-37, they won't be able to find your posting.  Thank you!

cournot

OK,不过CD的搜索引擎可否设置成包含字段的搜索方式，

then if someone is searching for gwd-28-37, they will still be able to find your posting. 

即POST的帖子含有该题，但还有其他题，搜索人不仅可以看到该题，还可以看到这套题的其他题，这样节省了论坛帖子的空间，也节省了搜索人时间，并且搜索人在同一帖子可以看到更多东东。

[此贴子已经被作者于2006-6-4 13:08:25编辑过]

yaoyao99

Don't think the search enginee is that flexible, unfortunately.

cournot

ok,I will follow your advice.