CR Help by Farbood

Going through free CR lessons by Grockit here. I think they're nice lessons, but I could be biased. Anyone else think Farbood Nivi is totally hot? ;)

Did some more Work questions today. Will practice some more TSD questions, and then go through FCs.

CR update

So after going through all these CR notes on the net, I tried 3 questions from OG12 (not too many left to choose from...yey!) - one of each type (S, W & A). Got the assumption question wrong, the others were right. Hmmm...going to practice slowly (i.e. identify question type, conclusion, premise(s) and imagine any linking assumptions) from my BTG account.

Wish me luck!

Edit: Tried a few BTG questions, and some other questions online...Hmmm...still not feeling satisfied, although I do have a methodical way of answering the questions now. *sigh*
I should go through other question types, and then do the remaining CR questions from OG12, right?

Improving first, then moving forward.

Did not finish OG12. Reason is that I was going through my error log and realised I was getting certain types of questions consistently wrong in CR and SC - thought I should work on them. Posted it on GMATClub.com to see if anyone could give me some tips on improving my accuracy.

For Quant, I've mainly been making silly mistakes. Also, I haven't gone through my FCs in really long so have forgotten some stuff like Compound Interest formula and how to calculate SD. Need to do that.
In addition, I've been getting Triangles questions wrong - so plan on going through this series on Triangles tricks.

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Have spent most of today working on getting my basics right in CR. Will post an update soon.

GMAT love coming your way!

PS. Will take a month off from work before the GMAT because the way my work works, THIS is not going to work out! :) I've spoken to my boss and he said it'll not be an issue. So I am taking GMAT end of Jan, hopefully by 27th Jan 2011. I want to get my 800 already. :)

The beginning of reality.

Started OG12 this morning - 14 PS and 10 CR questions. Got 2 CR questions wrong. And I'm going to get excited every time I get a Verbal question wrong from now on, esp CR. Because if I get an OG question wrong, it will help me learn where I'm going wrong! :)


Also done with Speed Math chapter 9, still going through chapter 10.

Spent some time in office doing questions from BTG's articles. Was fun! :) I need to get back in the groove now, still hoping to get done with GMAT by mid-November. Wish me luck guys, I neeeed it!

Happy Gmatting!

Kaplan Permier: Blue Quiz

Completed Kaplan Premier's Blue Quiz today. Scored an 87% overall. Got 26/30 right. Wrong - 2 CR (DOUBT IN #20 - ASK A KAPLAN INSTRUCTOR), 1 SC (idiom - as many...as) and 1 DS (ASK FRIEND!).

An Important Sequence & a CR link

Here's a type of Sequences question I wasn't aware of, till now.

Repeating Patterns

Many times, repeating patterns will yield a remainder question.

The first term of a sequence is  -2 and the second term is 2. Each subsequent odd term is found by adding 2 to the previous term, and each subsequent even terms is found by multiplying the previous term by -1. What is the sum of the first 669 terms?

Clearly, we are not looking to enter all 669 terms and see what the last one is. But, we can do a few and check out the pattern.
n = 1, = -2
n = 2, = 2
n = 3, = 4
n = 4, = -4
n = 5, = -2
n = 6, = 2
Since we can see that the pattern will repeat every 4 terms, we can solve for the remainder after dividing 669/4. Since 4 goes into 668 evenly, we know that the value will be equivalent to that of the first term, which = -2.

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Also discovered a whole host of useful GMAT CR articles on BTG. Read the first two (in chronological order) and found them pretty useful. Even assumptions are of two types: sufficient and necessary! And the question type (by a subtle change in wording) can change the answer! Damn. Those 2 are definite re-read material.

CP #7

From GMATHacks again.

Commensalism is any relationship between two living things in which one benefits and the other is neither helped nor harmed. Oxpecker birds are commensal species that flock with the large mammals of the African Savannah. They feed on ticks, fleas, and flies that are attracted to the mammals' fur. Which of the following, if true, can most reasonably be inferred from the statements above?
(A)	Oxpecker birds are neither helped nor harmed by the large mammals of the African Savannah.
(B)	Ticks, fleas, and flies are commensal species in their relationship with both oxpecker birds and the large mammals of the African Savannah.
(C)	No species exist in a commensal relationship with oxpecker birds except for large mammals of the African Savannah.
(D)	In commensal relationships, the smaller of the species in the relationship usually benefits while the larger is neither helped nor harmed.
(E)	Preying on small creatures drawn to the fur of the large mammals of the African Savannah does not significantly affect those mammals.

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Answer: E

This is an inference question. The passage suggests that, since oxpecker birds are commensal species with large mammals, they benefit from the creatures that are attracted to the mammals' fur, but the mammals themselves are neither helped nor harmed by the relationship. Consider each choice, looking for a reasonable inference:

(A) This choice gets the commensal relationship exactly backwards.
(B) This is clearly wrong. If oxpecker birds feed on ticks, fleas, and flies, clearly the ticks, fleas, and flies are neither benefiting nor neutral in their relationship with the oxpecker birds.
(C) This choice is too extreme. The passage only describes this relationship; it doesn't tell us that it is exclusive.
(D) This is also too extreme. It may be true in some instances, but the three sentences of the passage don't provide enough evidence to reasonably deduce this.
(E) This is correct. It merely restates the definition of commensalism in terms of the role of the mammals in their relationship with oxpecker birds.

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I know it's not a difficult question, but I've made the same sort of mistake on earlier questions too. I had used POE to come down to A & E. But, by then I had lost track of the question I guess, and chose A. A Veritas Prep GMAT Tip of the Week talks about such mistakes.