Tuesday, May 29, 2012

May 29, 2012 – Powers in the Quant Section in GMAT

While I have been working on the quant section, POWERS is one of the topics that is tested and on which questions can be expected. Below are a few pointers to keep in mind with regards to the Powers that I have been able to recollect and which I have read in a few quant related articles --:

1.                 Keep in mind the properties of Powers (Addition, Subtraction, Multiplication)

2.         0 is an EVEN number

3.         An even power is always positive, whether the base is positive or negative. 
             Eg :-- 
                       (-2)^2 = 4 and (2)^2 = 4

4.         An odd power retains the base's original sign.
             Eg :-- 
                       (-2)^3 = -8 and (2)^3 = 8

5.                 Adding and subtracting powers with the same base:
                        DON'T: add or subtract the exponents
                        Example: x3 + x5 ≠ x8

                        Do: extract the highest common factor.
                        Example: x3 + x5 = x3(1+x2)
6.        If you're not sure that you factored the expression correctly, check that re-expanding the brackets does return to the original expression. This is a method to cross-check and should be used if you have time and are unsure of your answer
7.       Like terms (same base and same exponent) can always be added/subtracted:
6a2 + 3a2 = 9a2

8.        Whenever one encounters an even root in the GMAT, it only represents the positive solution. Which is why x in the quadratic equation x^2-4=0 will equal ±2, but if it is stated as only √4 then it will equal 2 alone. By EVEN Root, the statement refers to square root or 4th root, 6th root and so on.

9.       In other words, both positive and negative roots must be considered if we placed the square root ourselves, as part of solving an equation, for example.

10.      If the root sign is already there to begin with, it signifies only the positive root (This is a mathematical convention).

Sunday, May 20, 2012

May 20, 2012 – The importance of time on a minute by minute basis

It has been quite some time, a month to be precise, since I last updated an entry here. The reason though was a valid one that being that I had a much needed vacation and got some time off. This was particularly needed to recharge the sagging batteries since the last unsuccessful admission application cycle which seemed to have sapped my energy. Hopefully this will refuel and fully recharge my batteries for this season.

I was fortunate to experience the transport services in the United Kingdom during my vacation. The most important takeaway from my experience there was the importance of time on a minute by minute basis. I missed a few trains and buses since I was late by a minute or two. That said, when I was before time the train / bus was running about 3-4 minutes late. An irony indeed :D !

It is not rocket science to link that the GMAT being an adaptive time based test makes one value the importance of time. That said, personally, I have experienced that though one does realize that one has only 75 minutes for the 37 Q / 41 V questions it is letting go that needs practice and more practice. Sometimes we just get stuck into a question for too long (too long can be anything from 4 minutes to 7 or 8 minutes). We feel like we might be able to solve the question but then it just does not happen. I recommend that if it is taking more than 3 minutes then it time to just make an educated guess and move on. It is better to guess on the DS than performing one on the PS.

What do I mean by letting go here exactly? So let me just explain it in a slightly more detailed manner. The 75 minutes are normally split into either a small question count or a minutes slot as per one’s convenience. I prefer splitting the number of questions to be completed / left corresponding to the minutes left on the test. For a tentative plan please find the illustration as below --:

Q.05 – 63 mins left
Q.10 – 52 mins left
Q. 20 – 33 mins left
Q. 30 – 14 mins left
Q. 35 – 4 mins left

I devised this during my first attempt since the time clock on the GMAT shows us the time remaining. I would advise you to devise your own strategy time clock for reference. I have observed that the question from 5 to 10 tend to be more intensive. My personal observation has been that the first 3-4 questions tend to be of Problem Solving and then the next 2-3 questions tend to be of Data Sufficiency. Also my own testing experience is that I tend to relax from questions 13 to 25 tending to miss the time and trying to increase my accuracy. I have decided that I have to consciously prevent this from happening again in my attempt this time. I will be taking care of this issue during my mocks as well.

I am working towards preparing a strategy for my preparation now. I know that I need to really work hard on my Quant side to push it to a score of 48 or 49 Q. The problem is that I know the basics but somehow am not efficient enough in the application.

I have a few things in mind for this issue. One is the concept of Ball-Parking. I attended the BeatTheGMAT webinar on the IR and during a session by the instructor from MasterGMAT he illustrated an example on this concept of Ball-Parking. I will try and understand more on this concept and provide an entry once I have a concise understanding of this interesting concept. Getting back to the table now to decide up on a good strategy to supplement and aid my preparation.