不明白了！DS中什么时候字母指代的是已知数？（关于 天山 4 和 天山 6 ）

jayhawk

是E， 才明白过来。 18， 27， 36。 有两个公约数。 3 和 9。 如果有3个员工， 符合A和B条件。 9个员工也符合A和B条件所以A和B加一起也不好使， 选E

tqbiao

以下是引用greatvampire在2005-3-8 20:37:00的发言：

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天山4-Q5:
A department manager distributed a number of pens, pencils, and pads among the staff in
the department, with each staff member receiving x pens, y pencils, and z pads. How
many staff members were in the department ?
(1) The numbers of pens, pencils, and pads that each staff member received were in
the ratio 2 : 3 : 4, respectively.
(2) The manager distributed a total of 18 pens, 27 pencils, and 36 pads.
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:
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答案选E我选B
我的前提是把x、y、z当作已知量
number of staff members = 18/x = 27/y = 36/z

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天山6-Q23:
In the xy-plane, point (r, s) lies on a circle with center at the origin. What is the value of
r2 + s2?
(1) The circle has radius 2.
(2) The point (v2, -v2) lies on the circle.
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:
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答案选D
明显把字母v当成已知量

这就矛盾了
同样是字母
为什么前一题的x、y、z是未知量而后一题的v确是已知量
不解
难道x、y、z长得更像变量
望赐教

我轻轻的告诉你，那个应该不是v是平方根号，这个问题在天上6-q20中已经存在了，估计是打印的问题！

greatvampire

似乎“出现在选项中当作已知”这点更容易让人接受

爱维的天

你問的問題很怪,但卻很好,我試著用這兩個問題回答,再請NN們補充,基本上,超過一個以上的變數我會認為是未知,在題目出現的我也會當作是未知,若出現在選項中的,我才會把它當已知....參考一下,

greatvampire

不好意思 可是这里我是为了对比啊 beautywawa jj

我真是被这个问题给confuse了

beautywawa

麻烦下次多题请分开发帖提问,一来方便讨论解题,二来方便搜索查找功能,谢谢唷!!

greatvampire

郁闷的时候要靠自己顶~~~

greatvampire

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天山4-Q5:
A department manager distributed a number of pens, pencils, and pads among the staff in
the department, with each staff member receiving x pens, y pencils, and z pads. How
many staff members were in the department ?
(1) The numbers of pens, pencils, and pads that each staff member received were in
the ratio 2 : 3 : 4, respectively.
(2) The manager distributed a total of 18 pens, 27 pencils, and 36 pads.
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:
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答案选E我选B
我的前提是把x、y、z当作已知量
number of staff members = 18/x = 27/y = 36/z

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天山6-Q23:
In the xy-plane, point (r, s) lies on a circle with center at the origin. What is the value of
r2 + s2?
(1) The circle has radius 2.
(2) The point (v2, -v2) lies on the circle.
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:
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答案选D
明显把字母v当成已知量

这就矛盾了
同样是字母
为什么前一题的x、y、z是未知量而后一题的v确是已知量
不解
难道x、y、z长得更像变量
望赐教

[此贴子已经被作者于2005-3-8 21:41:30编辑过]