Veritas Prep PS Forum Expert - Karishma - Ask Me Anything about Math

ok Karishma I have read your posts and found out that you are better at understanding the internal working of mathematics (QUANT) in connection with GMAT then anybody else in this forum. The problem with me is that this is my first ever CAT test in life so I went head on brute force with GMAT which is to "know all to solve all" but I think GMAT is ocean and this strategy is taking me nowhere. I have gone thru all the basic quant requirement from reputable resources and my concepts are fine.

so here is the problem i gave the GMAT club test and scored 8/31 correct and wrote a furious review about the club test but later when I reviewed where I went wrong I figured out that, it is not the theory where I am missing the problem is something else.

I want to give you an analogy to understand what that is. Suppose an amateur starts to play chess what he will see is the pieces and how to move them but he will not know all the tactics. Maybe he will even lose the sight of pieces where they are placed amid game due to extreme concentration on some other part of the board. But it does not mean that his brain is dull it means that his brain is still not wired for that. what does wired means here is that he can not spot the common patterns quickly, yet.

The problem what I am facing is I am doing well in 600-700 level range but when it comes to 700+ I think I am not wired and I think one cannot be wired for the 700+ since each question is a stand-alone question and requires some cognitive thinking which takes time. Maybe after going through 100s of 700+, I could say there is a pattern too but for time being I have to stand at 700+ and invest some brain there to find the pattern which costs time in the actual test. I don't have time to go thru 100s of 700+ to wire my brain so what I have decided is I want Q49 for which best range to practice questions is 600-700.

I have gone thru all OG tags 600-700 here is where I want your help I want you to spot me what type of question bank I should practice to know all common pattern in Q49 range so that I don't have to lose time in making the mental picture and doing the cognitive thinking.

Side note.
I am not running away from nor I am afraid of 700+ given more time I could crack them easily but I am being smart here by saving time, rather than getting the punch on the face and learn from it "I want to float like a butterfly and sting like a bee".

Ah! The first query on my thread is a challenge!
What I get from your post is that you are looking to cover all patterns (or at least as many as you can) of medium-difficult level. For that, OG doesn't really give an accurate picture. GMAT Official practice exams will do a much better job (though not exhaustive). Also, standard test prep companies take care of introducing most patterns over their coursework.

But if I am to be honest, I don't really believe in "questions are made keeping a finite number of patterns in mind" theory. I believe in concepts. After that, give me a question of any new pattern and I will solve it. 700+ level question are harder only because it is more difficult to recognise the concept being tested in them. Application of the same may not be troublesome at all.

Karishma-Thank you for taking the time out to answering questions. I have been your follower of your solutions since many years and must say you are a star when it comes to GMAT. So here are my questions.

1. Can you share inputs on how to get to V44+ from V35/36?
2. How do I move from Q47/48 to Q51?
3. How do I get to 90-100% accuracy both in verbal and quant?

Also, I am guessing you would be having a high score to your credit?

Thanks.

Hello Karishma,

I am realty struggling with getting off with quant,can you help me decide a startergy what should I practice to start off,what resources to use and build up my quant skills. Thanks

Posted from my mobile device

Shrinidhi,

Please provide me details on your current level of prep in as much detail as possible. Here is an idea of things you need to cover:

Have you taken a prep test? If yes, what was your score? Your Q/V split? Your accuracy in easy/medium/hard questions?
Have you run through the complete curriculum of a test prep company? OG?
How comfortable are you with basic Arithmetic, Algebra etc?

Thank you Karishma for taking your time out and helping us.

I recently gave my GMAT and got a very low GMAT score. I was more disappointed with my Q 47. On the test day, I took more than 2 mins on tougher questions especially DS. I had problems solving DS since the start of my prep. GMAT club quant tests helped me a lot, but I always fear on DS that I might be missing something else. "Should I plug more ? Did I plug in enough ?" And that attitude ultimately killed my test.


Even though I practiced many questions on this club on Functions and Inequalities, as I am uncomfortable with those topics, on test day, GMAT threw surprises and I succumbed.

Shed some light on to how to stop being overcautious on DS and few tips on handling Functions and Inequalities questions.

Posted from my mobile device

HI Karishma

It really is helpful to read all of your posts. I have made it a habit to go through your posts everyday, and it really helps me a lot.

So The problem I am facing right now is time management. I have my Gmat on the 4th of November.
My lowest score on the Quant gmat club tests was 44 and the highest was 49. I mostly stay around 47-48-49.

According to my targets, I have to score Q50.
The only topics on which I have not solved 700 level questions are Probability, P and C, Statistics and coordinate geometry. I am slightly under confident in Geometry.
So out of these topics, what should I ideally cover?
I would like to believe that my basics on these topics are not bad.

Also it would be great if you could help me from where I could cover any of these topics efficiently.

Regards

Hi karishma can you help me with following question/ general approach for following type of questions

The probability of the occurrence of event A is 0.50. The probability of the occurrence of event B is 0.40. What is the range of probability A will not happen AND B will not happen?

A. 0.1≤p≤0.5
B. 0.4≤p≤0.5
C. 0.5≤p≤0.6
D. 0.1≤p≤0.6
E. 0.2≤p≤0.5

Hello Veritaskarishma,

If you can suggest me A proper Plan/strategy to ace Quant(PS and DS) (i.e >90% accuracy)from scratch,it would be great.Like how to start,which resources to use, practice questions etc...
Thanks

Here is the thing about DS questions - people love to solve them by plugging in numbers and I think that strategy often backfires. Until and unless one is super fast in one's calculations and has an intuitive understanding of number properties and how the behaviour of numbers changes at each transition point, one should not use number plugging. But then, if one does have all those skills, number plugging is not required. Hence, all in all, in my opinion, it is a lose-lose proposition.
I am not saying that number plugging is useless:
- I agree that for easier questions, number plugging could work (though it might take more time than the more logical approach).
- Also, for harder questions, it can help you understand the problem and figure out the logic/pattern.
- It also helps you weed out special cases such as n = 0.
But the dependence we often have on this approach since it seems easy to follow is unwarranted.

Focus on the logic being tested in a question and the issue of "being overcautious" or "missing something" will not arise. Send me some links of functions and inequalities questions that gave you a hard time and I will tell you what I am talking about.

Hey Nitesh,

Glad to hear that!

As for the topics mentioned by you:

Step 1: Work on Geometry. Be brilliant at basic concepts such as 30-60-90 and great at others such as polygons inscribed in circle etc. Co-ordinate geometry is gaining ground in GMAT so it is a good idea to be comfortable with it. I think it is extremely easy once you understand the basic things such as drawing lines, how small changes in slope and intercept change the line etc, relation between these concepts, distance of points from centre and its relation to pythagorean theorem etc. I have discussed quite a few Geometry concepts on my blog (if you wish to check them out) though you will need to look for them in order starting from the oldest page.
https://anaprep.com/blogs/

Step 2: I love Stats! I know that is not a good enough reason to focus on it but the point is that it is quite conceptual and questions on it are fun! I have discussed most of the Stats relevant topics on my blog:
https://anaprep.com/blogs/
and the video here: https://youtu.be/W-qhIZ29UIs
https://youtu.be/0E6FQMzQVj0

Step 3: Combinatorics - Too much time spent here may not lead to much. Say if you get a 600-700 level question on it, you should not miss it. But a 700+ level question on it, give it your best shot and move on. There are tiny things, one word, that could change the question entirely from what you might have come across before. The entire approach would change in that case. Hence, I feel that the topic is just a wee bit too fickle to invest a lot of time in.

Here is the link to its videos though:
Video on Permutations: https://youtu.be/LFnLKx06EMU
Video on Combinations: https://youtu.be/tUPJhcUxllQ
Video on Probability: https://youtu.be/0BCqnD2r-kY

Solution:

P(A) = .5
P(B) = .4

You need to find P(Neither will happen). Think about the corresponding sets concept. Neither is given by Total - n(A or B)

P(Neither will happen) = 1 - P(A or B) = 1 - [ P(A) + P(B) - P(A)*P(B) ]

We don't know the relation between the events A and B so we don't know what P(A and B) is. Try to think of this in terms of the venn diagram.

To minimise neither, we need to maximise P(A or B). So A and B should have minimum overlap.
Assuming A and B are mutually exclusive events, P(A and B) = 0
P(Neither will happen) = 1 - [ P(A) + P(B) - P(A and B)] = 1 - [.5 + .4 - 0] = 0.1

To maximise neither, we need to minimise P(A or B). So A and B should have maximum overlap.
Assuming B is a subset of A , P(A and B) = 0.4
P(Neither will happen) = 1 - [ P(A) + P(B) - P(A and B)] = 1 - [.5 + .4 - .4] = 0.5

Answer (A)

Apurva, how to ace Quant is a very generic question - the answer would need a thesis of 25,000 words! I will try to condense the main points for you in a few days!

A greater number of newspapers are sold in Town S than in Town T. Therefore, the citizens of Town S are better informed about major world events than are the citizens of Town T.

Each of the following, if true, weakens the conclusion above EXCEPT:


(A) Town S has a larger population than Town T.

(B) Most citizens of Town T work in Town S and buy their newspapers there.

(C) The average citizen of Town S spends less time reading newspapers than does the average citizen of Town T.

(D) A weekly newspaper restricted to the coverage of local events is published in Town S.

(E) The average newsstand price of newspapers sold in Town S is lower than the average price of newspapers sold in Town T.

Request to all forum users:

I am one of the forum experts on the PS forum. If you would like me to take a look at any question on this forum, please mention it on this thread.

Since I receive 100s of mails everyday in my mailbox, unfortunately, it becomes very difficult to follow up on every query even if I am tagged on it. I do take a look at this thread on a daily basis and hence will certainly get to your query if you mention here.

Thank you!

Hi https://gmatclub.com/forum/memberlist.p ... asKarishma,
Thanks for replying to my PM. As suggested , i am pasting URL's of few word problems to start with. I will be sharing lot of problems soon but i will wait for you to sort them out and help me to see how I could have converted it into an equation. After a few, may be I will start seeing how to convert into equations on my own.

https://gmatclub.com/forum/of-the-stude ... 95246.html
https://gmatclub.com/forum/working-simul ... 07314.html
https://gmatclub.com/forum/in-order-to-c ... 40555.html
https://gmatclub.com/forum/gmat-diagnos ... 79356.html
https://gmatclub.com/forum/gmat-diagnos ... 79358.html
https://gmatclub.com/forum/a-chess-play ... 52608.html
https://gmatclub.com/forum/if-x-a-and-b ... 01946.html

Hi VeritasKarishma

I had a query wrt your articles on the made easy series.

Q. IN how many ways can A,B,C,D,E,F be arranged in a circular table provided that A cannot sit next to D or E?

This question is a slight variation in comparison to your question on the Combinations Article 3: Circular Arrangements.

I recon that it is slightly complicated.

Here was my approach:

If only
1. D/E is selected: 2 ways * 6 ways( 3c2 ways of choosing people to be beside A and 2! ways of arranging them) * 2 ways( the other people arrangement)

2. D and E both are selected:
3c2(out of remaining 3 people, 2 are selected)* 2 ways (those 2 people are arranged) * 2 (D,E are arranged in remaining places)

3. A is not selected: 4!

SO total possibilities:

24+ 12+24= 60 ways.

Am i correct in my reasoning ?
and is there any simpler and faster way to do this question?
Looking forward to your reply!


Regards
Nitesh