Quant Complexity
I haven't written in awhile, but I wanted to post a new entry that may help people with their timing on the exam.
We know that harder, more complex questions tend to take more time. But why do they take more time? The two main reasons that I noticed from my practice were:
1) Unfamiliarility with the fundamentals of the question
2) A question asked in an unfamiliar format
The first has ramifications in deciding when to quit on a question and move on to the next question. In particular, if you do not understand the fundamental idea behind the question or you have very little knowledge of that area, looking at the question for 3 minutes or 5 minutes will not provide you with a sudden epiphany on the topic and you will have just wasted precious time.
In practical terms, it is wise to spend a few seconds on every question to ask yourself what the fundamental topic is. Is this just another rate question? An even/odd number property question? A combination question? Then ask yourself how familiar are you with that topic? If you are weak on that topic, be ready to move on if the question appears to be a hard one. Doing so can shave off minutes in the long run.
The second has ramifications for finding the answer and solution approach more quickly. For example, let's say you understand the basic mixture formula and you get a simple PS question concerning mixtures. You can probably apply the formula as is and solve the problem. Now, what if that question were posed to you with a chart containing certain percents for ingredients - you would have to be able to quickly interpret the chart for the data. Next, you come across a mixture DS problem. How does the formula apply now? Does the formula apply at all?
Certainly, you may be able to solve each of these variations given enough time, but the time constraints on the real exam can severely punish your score. I believe this second complexity is where you can actively and effectively mold your studies to attack quant problems. I did not realize this myself until the last few days before the exam so I did not utilize it effectively. The idea is simple: reducing the complexity with unfamiliarility of the question format and how the question is asked can help save precious seconds on each problem because you can skip the mental work associated with understanding the question.
Here's how I did this:
1) Pick a particular math fundamental (hopefully one which you are weak at)
2) Go through your resources for questions and find questions that involve that fundamental.
3) In a log book, copy these questions for that topic, but only copy the ones that are asked in a format that has not already been noted earlier (i.e. you do not already have a question copied that is basically the same question)
4) Write down the answers for each question and how the fundamental topic was applied and used to solve each.
5) Review your notes in fundamental topic sets
For me, mixture questions were a bit hard at first so I went through the Kaplan 800 book, OG11, and the PR math review book and wrote down each question that had a variation from the others. So in my log, I had a PS mixture question, a DS mixture question, a ratio mixture PS question, a mixture PS question with fractions instead of percents, etc etc. There were several PS mixture problems that were similar to one another, but there was no need to copy all of them since they require the same knowledge to understand. This log helped me expand my knowledge of how I could apply the mixture formula and going into the exam, I was confident that if I saw a mixture problem I could solve it fairly quickly.
Note that this is particular useful for questions where a formula can be applied. For example, I had a log section on category overlap questions, mixture problems, arthimetic progression problems, work problems and rate problems.
Understanding these two complexities also has ramifications on what you should study. Many people are tempted to study topics that have a very small chance of appearing on the real test. For example, in the 400 or so quant questions in OG11, there was only 1 minor arc geometry question. The chances of you seeing a question about a minor arc on the GMAT should be fairly slim; however, there are many, many mixture problems, rate problems, work problems etc. So it is smart to build a strong foundation on these fundamentals before studying more obscure stuff that have very little chance of appearing on the real exam. Studying specific quant fundamentals organized in a log like I've suggested above helps to build this foundation.
I scored 49 on Q and saw 0 combination and permutation problems. My other friend who scored 760 also got a 49 on Q and he did not see any questions on C&P either. Keep that in mind when deciding what topics to study.....