请教几道prep上的题

和上次感觉一样，prep上的题目还是挺难的，看来要好好看看jj了，请教几道题，谢谢大家

1.In the fraction x/y, where x and y are positive integers, what is the value of y?

 (1) The least common denominator of x/y and 1/3 is 6.

（2）x=1.

Answer: E

2.If n denotes a number to the left of 0 on the number line such that the square of n is less than 1/100, then

  the reciprocal of n must be?

Answer: less than -10  (Why not greater than 10?)

3.If m and r are two numbers on a number line, what is the value of r?

(1) The distance between r and 0 is 3 times the distance between m and o.

(2)12 is halfway between m and r.

Answer:E

4.Is xy>0?

 (1)  x-y>-2

 (2)  x-2y<-6

Answer: C

5.Is [(x-5)^2]^1/2=5-x?

 (1) -x|x|>0

 (2) 5-x>0

Answer

6. A hiker walking at a constant rate of 4 miles per hour is passed by a cyclist travelling in the same derection along the same path at a constant rate of 20 miles per hour. The cyclist stops to wait for the hiker 5minutes after passing her , while the hiker continues to walk at her constant rate. How many minutes must the cyclist wait until the hiker catches up?

Answer: 20

1.我怎么觉得（1）可以呢，如果最小公分母是6的话，那y不是=6么？

2. n denotes a number to the left of 0, so can't be greater than 10

我要先加班了，一会再做起他的

谢谢楼上

第一题我也是这么想的，第二题中的to the left of 0是什么意思啊？

呵呵，感谢LS

剩下的几道能帮帮忙吗？

Please please search for existing discussions before you post your questions.

2 = #155

http://forum.chasedream.com/dispbbs.asp?boardID=22&ID=150752

3 = #251

6 = #23...

[原创]GMATPrep 数学讨论题库汇总I！  by cd小兵       点击此处查看

[原创]GMATPrep 数学讨论题库汇总II！  by cd小兵       点击此处查看

谢谢yaoyao~~~