For the final 5 days, I do not recommend taking a practice test every day. During my last 2 weeks of study I only used the OG. Since GMAT Prep only has 2 tests, you would have to take practice tests from some other study book, which is probably not a great idea at this point - they will be either to...

How do we know that xy=120? We only know that (x+1)(y-10)=120.

All we know is that it went up and then it went down. Plugging in simple numbers is the easiest way to think about it. If it went up 10% from 100 to 110, then knowing that it went down more than 10% is insufficient to determine if now we are less than 100 because if its only a small amount more, say...

x, y, k

Let's see if papgust can get this one.

If x,y, and k are positive numbers such that 10x/(x+y) + 20y/(x+y) = k, which of the following could be a value of k?

10
12
15
18
30

Scale that measures

This is an OG question. On a scale that measures the intensity of a certain phenomenon, a reading of n+1 corresponds to an intensity that is 10 times the intensity corresponding to a reading of n. On that scale, the intensity corresponding to a reading of 8 is how many times as great as the intensit...

I am no grammar expert, but this is my understanding of the distinction. In general, "like" serves as a preposition and uses one noun to describe another or to compare one noun to another. For example, "He speaks like a fool". We are comparing "He" and "fool"....

When I pulled out the 10^2, I got (10^6 - 1)/(10^5 - 10), which I could not manipulate to one of the answers. I guess at that point you can kind of eyeball it and see that the -1 and the 10 are insignificant, so 10^6/10^5 will give you 10. Is there a better way? Can someone explain?

Got it, thanks. I don't know why I had in my mind that it was a perfect square question.