Chinagmat：四月GMAT考试机经真题
Chinagmat：四月GMAT考试机经真题Question: 1题目If x and y are integers, is x2 1 > y2 + 1?(1) x > y(2) y > 0选项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: C +w：ivyexam 获取更多保分机经题库 (GMAT保分730; GRE保分330 ;TOEFL保分100) 注释：条件(1)(2)同时成立时，x>y>0，又因为x和y都是整数，所以为x2 y2 3，不等式成立。单独条件无法论证，如果x=2, y=-5，等式不成立，（1）不充分；当x=2, y=2，等式不成立，（2）不充分，所以选择C。Question: 2题目 Is s + t > 0 ?(1) s t > 0(2) s2 t2 > 0选项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: C +w：ivyexam 获取更多保分机经题库 (GMAT保分730; GRE保分330 ;TOEFL保分100)注释：因为(2) s2 t2 =(s+t)(s-t)>0，则s+t>0，s-t>0或s+t<0，s-t<0；所以要使s+t>0，则s-t>0；所以条件(1)(2)同时成立时，不等式才成立，单独条件无法论证，选择C。Question: 3题目Is r > t?(1) 5r 5t = 2(2) 5r + 5t = 10选项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: A +w：ivyexam 获取更多保分机经题库 (GMAT保分730; GRE保分330 ;TOEFL保分100)注释：(1) 5r 5t = 5(r-t)=2，所以r-t=2/5，所以r>t，条件充分；(2) 5r + 5t =5(r+t)=10，所以r+t=2，无法推出r>t。所以选择A。Question: 4题目Which of the positive numbers x or y is greater?(1) y = 2x(2) 2x + 5y = 12选项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: A注释：因为x和y都是正数，所以(1) y = 2x条件充分，可推出y>x；(2)2x + 5y = 12，x=1, y=2，或x=4, y=4/5等都是方程的解，无法确定x和y大小，条件不充分，所以选择A。Question: 5题目Is x5 x4 > x3 x2?(1) x > 1(2) x4 > x3选项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: A注释：由x5 x4 > x3 x2得x4(x-1) > x2 (x-1)，当(1) x > 1时，x4>x2，条件充分，等式成立。(2) x4 > x3只能推出x0，条件不充分。所以选择A。Question: 6题目In the rectangular coordinate system, does point P lie above line ? ?(1) Line ? does not intersect quadrant II.(2) The x-coordinate of P is 1.选项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: E注释：P点在直线?上方。(1)直线?不经过第二象限，只有P点在第二象限才能保证P点在直线上方，条件不充分。(2)P点的横坐标是-1，则P点可能在第二、三象限，不能保证在直线上方。如果两条件同时成立，但若P点在第三象限，也可能在直线下方。综上，选择E。Question: 7题目If line k is in the xy-plane, is the x-intercept of line k less than the y-intercept ?(1) The x-intercept of line k is negative.(2) The slope of line k is negative.选项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: E注释：直线k的x轴的交点小于y轴的交点？(1)直线k与x轴的交点为负，因为与y轴的交点也可能为负，无法判断大小；(2)直线k的斜率为负，如果直线经过二三四象限，则可能与x轴y轴的交点都为负，无法判断大小。所以选择E。Question: 8题目If ? is a line in the rectangular coordinate system, does ? intersect the negative y-axis?(1) ? contains a point (r,s), where r > 0 and s < 0.(2) The slope of ? is positive.选项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 suf
