[720 Q49 V40] My Blog: Errors and lessons learned

mayonnai5e · Posted: Tue Nov 13, 2007 12:17 pm Post subject:

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.....

ajaypatil_am · Posted: Sat Nov 17, 2007 10:56 pm Post subject:

Hi mayonnai5e,
Thanks for all your posts.It is really helpful for person like me who want to score 700 + in GMAT but, extermely weak in centain areas like RC

Thanks Again,
Ajay[/size]

gmat killed me · Guest

that was one long ass explanation...

how are u suppose to do all that under a minute and half.. in supreme stress and time constraints..

i might as just move to antartica

mayonnai5e · Posted: Mon Nov 26, 2007 4:19 pm Post subject: Re: dead

beatthegmat · Posted: Mon Nov 26, 2007 8:00 pm Post subject: Re: dead

Leonard C · Posted: Tue Dec 11, 2007 4:43 am Post subject:

Hey mayonnaise ... great to hear you did well on the GMAT - congrats! I had been tracking your blog quite closely for a while and was hoping to sit the dreaded exam around the time you were going to sit it, but ended up breaking my arm and so had to take a couple months off to recover (I couldn't hold a book, much less write or type or study!).

Anyway, I'm back on to it now and it looks like your study program really paid off. I wonder though, looking at your scores, whether if you could go back and do it all over again whether you would do study as much as you did in Q vs V?

The reason I ask is that I have recently received the MGMAT math books I purchased from Amazon. I note that their practice questions are extremely long, and also very different to the quant questions in the OG. What are your thoughts on the MGMAT questions vs the OG or real GMAT quant questions? Is the time required to gett up to MGMAT standard in quant better spend revising verbal?

Stacey Koprince · Posted: Tue Dec 11, 2007 11:45 am Post subject:

Just an FYI that the math questions in our red strategy guides are not GMAT-type questions (you'll see most aren't multiple choice, etc). They're not written to mimic the test - they're written to test you on the math principles.

Most people do not need to do all of the math questions in the red strategy guides - you do the ones that you need to do, based on your own strengths and weaknesses, to make sure you know the principles tested on the exam. Then, when you do GMAT-type questions (or real OG questions), you actually know all of the stuff you need to know to answer those questions.

Also, when deciding what to do vs. what not to do, factor in the score you hope to get. If you want a 700+ (90+ percentile), then you need to do everything. But if you want a 650 or a 600, you don't need to do everything - you can get away with studying deeply the things that are more prevalent and only lightly studying the things that are less prevalent.

mayonnai5e · Posted: Sun Dec 16, 2007 10:12 am Post subject:

Sorry for the late response, but I do feel the MGMAT questions are worth studying. The reason is that the MGMAT questions are very difficult in that they are multi-layered and test many concepts (often in the same problem). This means that in order to complete them in sufficient amount of time, you are forced to think faster and more quickly evaluate the possible solution paths. Doing so will help you organize ideas and concepts faster on the real exam. It is similar to how people work their high jump by doing power movements with weights on so that when they take off the weights they feel much lighter and can jump higher - It's great mental training.

However, one caveat to this is that I feel some (not all) of the MGMAT Q questions are really offbase. They are unlike any question I've seen in any OG book nor any official CAT (GMATPrep/PowerPrep). During my studies, I evaluated every MGMAT question and determined which ones I felt were similar enough to official questions to warrant further study. Or if I felt a particular question tested my understanding of a particular topic in new ways I would also study it.

There were several that I threw out completely because I thought they were ridiculous questions. One example was a long winded word problem concerning compound interest. This question basically took the simple formula, convoluted it within a paragraph long question, required the test taker to do some algebraic manipulation, change the formula back into the basic compound interest formula, then indicate how many days the original amount would grow to certain amount and what day of the week you should take your money out.

I think the best course of action with regard to these questions is to do an evaluation for each question and determine whether you feel it is something that you may actually see on the GMAT.

beatthegmat · Posted: Mon Feb 11, 2008 4:28 pm Post subject:

In an effort to retain the integrity of mayonnai5e's blog, we have decided to lock down this thread. You can still post your questions in the 'GMAT Strategy' area.

Thanks!

mayonnai5e · Posted: Thu Apr 03, 2008 1:54 am Post subject:

Hello everyone, it's been a very long time since I last posted a blog. I just posted a reply to a thread by Enginpasa and I thought my reply was significant enough to post here on my blog so here it is:

Understanding SC:

For SC, one of first things I did when reading the sentence was to think about the meaning that the sentence is trying to get across. Don't focus on the specific words, but instead focus on the idea. If you are trying to communicate something to someone you would first think of the idea, formulate what you want to get across, determine how you want to convey that message then find the words and grammatical structure to do so. I found the performing those initial steps before immediately jumping into the "rules" helped me get a clearer understanding of which sentence was the best for clarity and conciseness.

For example, I could say any of the following:

* personally, i'd prefer to go to the movies tonight actually
* actually, i'd prefer to go to the movies
* i'd prefer to go to the movies actually
* i'd personally prefer to go to the movies
* i'd actually prefer to go to the movies

What was the original intent of the sentence and what was the idea being conveyed here? What can you infer from the topic at hand based on word choice (i.e. prefer, actually). You can tell there is a debate going on about what a group of people want to do tonight. You can also tell the individual is providing his preference as to what he/she wants to do.

Now which of these sentences is most clear? Which is the most concise? The difficulty in SC is that the writer adds in intentional errors, but if you can understand the idea and message you are halfway there. In fact, understanding the message helps by making the errors in the sentence all the more glaring. [/u]