【Help！】GWD十三套里的第13套数学，有几题弄不明白。。附上题目和答案～TX们进来瞧瞧

Naiveer

Q7:
For a certain race, 3 teams were allowed to enter 3 members each.  A team earned 6 – n points whenever one of its members finished in nth place, where 1 ≤ n ≤ 5.  There were no ties, disqualifications, or withdrawals.  If no team earned more than 6 points, what is the least possible score a team could have earned?

A. 0
B. 1
C. 2
D. 3
E. 4

这题答案是D。我不是很明白题目的意思，所以无从下手。。

————————————————————————-

Q13:
Is the measure of one of the interior angles of quadrilateral ABCD equal to 60 degrees?
(1)   Two of the interior angles of ABCD are right angles.
(2)   The degree measure of angle ABC is twice the degree measure of angle BCD.

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.

这题答案是C。我自己做出来的答案是E。因为我觉得另外两个内角的情况有可能是【60度，120度】和【45度，135度】的情况。

——————————————————————————

Q17

图发不上来。我用文字形容一下吧。有两个圆，一个大圆包住一个小圆，大圆的一条水平的直径为AE，小圆和大圆相切于A点，小圆半径为AB，小圆和AE的另一个交点为D，namely ABCDE在同一条直线上。

In the figure, points A, B, C, D, and E lie on a line.  A is on both circles, B is the center of the smaller circle, C is the center of the larger circle, D is on the smaller circle, and E is on the larger circle.  What is the area of the region inside the larger circle and outside the smaller circle?
(1)   AB = 3 and BC =2
(2)   CD =1 and DE = 4

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.

这一题答案是A。我自己算出来是D来着。。为嘛啊为嘛是A捏。。。。

————————————————————————————
Q23:
In the decimal representation of x, where 0 < x < 1, is the tenths digit if x nonzero?
(1)   16x is an integer.
(2)   8x is an integer.

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.
答案是B

Q33:
In the decimal representation of x, where 0 < x < 1, is the tenths digit of x nonzero?
(1)   16x is an integer.
(2)   8x is an integer.

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.
答案是A

这两题自相矛盾了吧。。估计答案23题答案有错。。我觉得应该两题都是B来着。。

——————————————————————
Q35:
Stations X and Y are connected by two separate, straight, parallel rail lines that are 250 miles long.  Train P and train Q simultaneously left Station X and Station Y, respectively, and each train traveled to the other’s point of departure.  The two trains passed each other after traveling for 2 hours.  When the two trains passed, which train was nearer to its destination?
(1) At the time when the two trains passed, train P had averaged a speed of 70 miles per hour.
(2)   Train Q averaged a speed of 55 miles per hour for the entire trip.

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.

答案是C。我自己觉得是A。。

kakahbwyb

Q7，一个队最少拿多少分，三个人都第五名，（6-5）*3=3
Q13，楼主你思路不对。1、2都成立时候，就是一个梯形，90、90、60、120 。怎么会有45和135呢
Q17，我也觉得D
Q35，我也不明白啊