Tag Archives : Quarter Wit Quarter Wisdom

How to Identify Terminating Decimals on the GMAT

How to Identify Terminating Decimals on the GMAT

We know the basics of decimals and rational numbers.

-   Decimals can be rational or irrational.

- Decimals which terminate and those which are non-terminating but repeating are rational. They can be written in the form a/b.

-  Decimals which are non-terminating and non-repeating are irrational such as √2, √3 etc.

Can You Find the Correct Answer to This Tricky GMAT Question?

Can You Find the Correct Answer to This Tricky GMAT Question?

This is hard to confess publicly but I must because it is a prime example of how GMAT takes advantage of our weaknesses – A couple of days back, I answered a 650 level question of weighted averages incorrectly. Those of you who have been following my blog would understand that it was an unpleasant surprise – to say the least. I know my weighted averages quite well, thank you! For this comedown, I blame the treachery of GMAT because it knows how to get you when you become too complacent. The takeaway here is – no matter how easy and conventional the question seems, you MUST read it carefully.

Elementary, My Dear Watson!

Elementary, My Dear Watson!

While eagerly awaiting the kick off of season 3 of BBC’s Sherlock, let’s put our time to good use. Though we have already spent a lot of it speculating over what really happened to Sherlock (HOW did he come back?!), perhaps we can take a leaf out of his book and learn to notice little things in whatever is leftover. There is a good reason to do that – there are little clues in some questions that the test maker unwittingly leaves to bring clarity to the question. If we understand those clues, a seemingly mysterious problem could be easily unraveled. Let us show you with an example.

Hard Quadratic Equations

Hard Quadratic Equations

When faced with an unusual quadratic equation, some people waste a lot of time while trying to ‘split the middle term’. The common refrain is ‘I am just not good at it.’ Actually it has little to do with intuition and a lot to do with understanding how numbers work. If I am looking at a quadratic equation and am unable to find the required factors, I will go back to check my quadratic to see if it is correct rather than try to use the esoteric quadratic formula.

Integrated Reasoning - Cumulative Graphs

Integrated Reasoning - Cumulative Graphs

Coming back to Integrated Reasoning question types, let’s discuss a cumulative graph today. They are usually a little trickier than your usual line/pie/bar graphs since you have to focus on not the data points but ‘the change’ from one data point to another.  Every subsequent data point will be either above or at the same level as the previous data point.

'Which' vs 'That' Debate

'Which' vs 'That' Debate

I know I promised that I will bring you some tricky Integrated Reasoning questions this week, but I am really irked by the ‘which’ vs ‘that’ debate and would like to put it to rest once and for all. Hence, in this post I would like to talk about restrictive and non-restrictive clauses, about ‘which’ and ‘that’, about when to use a comma and some other such things.

IR Questions: Multi Source Reasoning

IR Questions: Multi Source Reasoning

Now that we have seen some basic Integrated Reasoning question types, let’s start working on tricky Integrated Reasoning questions. The first set we would like to discuss is from GMAT Prep Software’s practice questions. This question has elements of RC, CR, PS and DS, all combined in one!

Critical Reasoning: Some Common Mistakes

Critical Reasoning: Some Common Mistakes

Now that we have seen some basic Integrated Reasoning question types, we will look at some tricky questions but not this week. This week, we would like to discuss a Critical Reasoning question. This question is simple and straight forward but still many people falter in it. The reasons for this are not hard to find. Let’s analyze this question in detail.

Integrated Reasoning - Multi Source Reasoning

Integrated Reasoning - Multi Source Reasoning

For the past couple of weeks, we have been talking about integrated reasoning. Today we will continue with that and take up a multi-source reasoning question. These questions often include substantial data and require you to make inferences based on it. They test your logical and reasoning aptitude so don’t get lost in the data. Review the given information and then jump on to the questions. Then come back to the relevant part of the given information and peruse it in detail.

Integrated Reasoning - Grasping the Graphs

Integrated Reasoning - Grasping the Graphs

Continuing our discussion on IR, let’s look at a graph today and learn how to infer from the data given in it. You may not need to do too many calculations because the options in the drop down menu may allow you to approximate i.e. the options may be quite far apart. Also, you will need to segment the graph into regions using imaginary vertical lines e.g. number of household spending less than 2 hrs at the mall in the graph given below.

Integrated Reasoning - Turn the Tables

Integrated Reasoning - Turn the Tables

Starting today, for the next few weeks we would like to focus on the ‘Integrated Reasoning’ section of the GMAT. The 1.5 yr old section of the GMAT has been giving jitters to many people. We have come across people with 48+ Quant scores but a 2/3 on the IR section. In my opinion, that’s a little strange. If you have strong reasoning skills, there is no reason you cannot apply those to this section as well.

Facing Too-Much-Knowledge Problems?

Facing Too-Much-Knowledge Problems?

Continuing our scrutiny of interesting standalone questions with important takeaways, let’s discuss today how too much knowledge can actually let you down. We often come across people wondering whether they should learn up the many formulas in permutation/combination, co-ordinate geometry etc. Our take on the question is a flat ‘No’. Formulas won’t take you far in GMAT, perhaps up to 600 but certainly not further. In fact, until and unless you have an eidetic memory or a Math PHD, chances are that knowing too many formulas will be a disadvantage. Let me show you why:

The Play of Words

The Play of Words

Some days back I came across a question which was a slight twist on a regular question type. The usual active voice of the sentence had been changed to passive but in such a way that the meaning had been altered. It was a lesson in DS as well as SC – read every word carefully. One word could change a 600 level to a 750 level one, a mundane everyday question to a smart question. We often see this interesting transformation in P&C questions but for that to happen in algebra was quite a delight. Let’s discuss that particular question today.

The Curious Case of the Incorrect Answer

The Curious Case of the Incorrect Answer

Many of us are hooked on to using algebra in Quant questions. The thought probably is that how can it be a Quant question if one did not need to take a couple of variables and make a couple of equations/inequalities. We, at Veritas Prep, love to harp on about how algebra is time consuming and unnecessary in most cases. But today we will go one step further and discuss how indiscriminate use of algebra can actually result in incorrect answers. Surprised, eh?

Dealing with the Third Degree

Dealing with the Third Degree

One of the basic things you need to know before you start your GMAT preparation is how to solve quadratic equations i.e. factorize the quadratic  and equate each factor to 0 to get the possible values that x can take. Today we will discuss how you can solve a third degree equation.

Say an equation such as x^3 – 6x^2 + 11x – 6 = 0.

When the Question is Harder than the Solution!

When the Question is Harder than the Solution!

Last week we looked at a question whose solution was quite hard to explain. This week we will look at a question in which the question itself is hard to explain (so no point worrying about the difficulty in explaining the solution as of now!) So why are we discussing such a question? Because it is certainly not out of GMAT-scope. It uses the concepts of relative speed and GMAT could give you some pretty intimidating questions at higher levels. So what should be your strategy when you come across a question which takes a minute or more to sink in? After you understand the question, first of all you should congratulate yourself that the toughest part is already over. If the question is hard to understand, the solution would be cake walk (well, at least it will feel like it).

When Does Order Matter?

When Does Order Matter?

I have to admit that probability is confusing. The problem is not so much that students find it hard to understand as that teachers find it hard to explain. There are subtle points in a probability question that make all the difference in the world and it takes a ton of ingenuity to explain them in a manner that others understand. You either get the point right away, or you don’t.

Using the Number Line

Using the Number Line

By now, you know that we like to discuss visual approaches to problems.  A visual tool that we have used before for solving inequality and modulus questions is the number line. The number line is also useful in helping us solve many number properties questions.

A few things to keep in mind when dealing with number line:

Plugging Numbers Without Using Transition Points

Plugging Numbers Without Using Transition Points

A few months back, one of our posts talked about knowing which numbers to plug-in in case you want to use the number–plugging method. To be more exact, we discussed that you need to find the transition points i.e. the points where the two sides of the inequality become equal. The transition points tend to reverse the relation between the two sides. For a detailed discussion of this concept, revisit this post.

Bewildered by your Verbal Score?

Bewildered by your Verbal Score?

Most people who plan to take GMAT seriously take a few prep tests, practice tests or mock tests, whatever you may like to call them. Usually, the tests are taken to gauge one’s current level i.e. to get an approximate idea of what one would score if one were to take GMAT that day. Of course, they have other uses too – practice in timed environment, build stamina, identify strengths and weaknesses etc. Usually, these tests are fairly accurate (with an error of up to 40-50 points in the total score). A recent phenomena has been much lower score (especially verbal) compared to the prep test scores (not among Veritas Prep students though – I will explain the reason for this soon).

The Matter of Squares

The Matter of Squares

Let’s look at a question today which encompasses most of what we have discussed in this topic. This will be the last post on this topic for a while now. We assume that after going through these posts thoroughly, if you come across any question on ‘this inscribed in that’, you should be able to handle it. Just a reminder, keep in mind the symmetry of the figures you are handling.

Questions on Circles Inscribed in Polygons

Questions on Circles Inscribed in Polygons

Last week we looked at questions on polygons inscribed in a circle. This week, let’s look at questions on circles inscribed in regular polygons. As noted earlier, it’s important to keep in mind that regular polygons are symmetrical figures. You need very little information to solve for anything in a symmetrical figure.

Questions on Polygons Inscribed in Circles

Questions on Polygons Inscribed in Circles

For today’s post, I have two questions for you – both on polygons inscribed in a circle. You must go through the previous post based on this topic before trying these questions.

And Now, the Other Way

And Now, the Other Way

Today we will work with circles inscribed in regular polygons.

We begin by considering an equilateral triangle whose each side is of length ‘a’. Recall that every triangle has an incircle i.e. a circle can be inscribed in every triangle. The diagram given below shows the circle of radius ‘r’ inscribed in an equilateral triangle.

Circle and Inscribed Regular Polygon Relations

Circle and Inscribed Regular Polygon Relations

As promised last week, let’s figure out the relations between the sides of various inscribed regular polygons and the radius of the circle.

Inscribing Polygons and Circles

Inscribing Polygons and Circles

Last week we looked at regular and irregular polygons.  Today, let’s try to understand how questions involving one figure inscribed in another are done.  The most common example of a figure inscribed in another is a polygon inscribed in a circle or a circle inscribed in a polygon. Let’s see the various ways in which this can be done.

Regular Polygons and the Irregular Ones

Regular Polygons and the Irregular Ones

Continuing our Geometry journey, let’s discuss polygons today. Some years back, I used to often get confused in the polygon sum-of-the-interior-angles formula if I had to recall it after a gap of some months because I had seen two variations of it:

Sum of interior angles of a polygon = (n – 2)*180

Geometry Diagrams for DS Questions

Geometry Diagrams for DS Questions

Let’s go back to geometry now. We will discuss how to use diagrams to solve DS questions today. Though we discussed a DS question in a previous geometry post, we didn’t discuss how the thought process used for a DS question is different from the thought process used for a PS question. To find whether a statement is sufficient to answer the question, you should try to prove that it is not sufficient. Try to make two cases which answer the question differently using the give information. If there are two or more different answers possible, it means the given information is not enough. Let’s discuss this with the help of an official question.

Or Just Use Inequalities!

Or Just Use Inequalities!

If you are wondering about the absurd title of this post, just take a look at last week’s title. It will make much more sense thereafter. This post is a continuation of last week’s post where we discussed number plugging. Today, as per students’ request, we will look at the inequalities approach to the same official question. You will need to go through our inequalities post to understand the method we will use here.

Plug Using Transition Points

Plug Using Transition Points

Let’s take a break from Geometry today and discuss the concept of transition points. This is especially useful in questions where you are tempted to plug in values. A question often asked is: how do I know which values to plug and how do I know that I have covered the entire range in the 3-4 values I have tried? What transition points do is that they give you the ranges in which the relationships differ. All you have to do is try one value from each range. If you do, you would have figured out all the different relationships that can hold. We will discuss this concept using a GMAT Prep question. You can solve it using our discussion on inequalities too. But if number plugging is what comes first to your mind in this question, then it will be a good idea to get the transition points.

Diagrams of Geometry - Part II

Diagrams of Geometry - Part II

Last week, we discussed how drawing extreme diagrams can help solve Geometry questions. Today we will see how to solve another Geometry question by making diagrams. The diagram can help you understand exactly what it is that you need to do; doing it will be quite straightforward.

Diagrams of Geometry - Part I

Diagrams of Geometry - Part I

Let’s continue with geometry today. We would like to discuss how drawing extreme diagrams can help you solve questions. Most GMAT questions are quite intuitive and hence our non-traditional methods are perfect for them. They are not typical MATH problems per se; instead, they are logical puzzles. If you can prove why some things will not work, it means whatever is left will work.

Graphs of Geometry - Part II

Graphs of Geometry - Part II

Let’s pick up from where we left last week. We had discussed a coordinate geometry concept using clock faces and had left you with a tough question. Today we will see how you can solve that question using the concepts discussed last week.

Graphs of Geometry - Part I

Graphs of Geometry - Part I

Let’s start with geometry today. It has some very interesting and intuitive concepts. We will discuss one of them today. It’s surprising how a little bit of imagination can go a long way in helping you solve questions. Let’s discuss the concept first. We will look at a question later.

Imagine a clock face. Think of the minute hand on 10. Ignore the hour hand for our discussion today. Say, the length of the minute hand is 2 cm. Its distance from the vertical and horizontal axis is shown in the diagram below (using the green and the red dotted lines). Let’s say the minute hand moves to 1. Can you say something about the lengths of the dotted black and dotted blue lines?

Assumption vs Inference

Assumption vs Inference

Another issue of assumption questions that merits discussion is the inference vs assumption confusion. On some questions, people find it hard to type the question as inference or assumption. Such questions often have the words ‘must be true’. Let’s discuss the two different cases:

Quarter Wit, Quarter Wisdom: Stuck in Assumptions Again

Quarter Wit, Quarter Wisdom: Stuck in Assumptions Again

There is a particular issue in assumption questions that I would like to discuss today. We discussed in our previous posts that assumptions are ‘necessary missing premises’. Many students get stuck between two options in assumption questions. The correct option is the necessary premise. The incorrect one is often a sufficient premise. Due to the sufficiency, they believe that that particular option is a stronger assumption. But the point to remember is that an assumption is only necessary for the conclusion to be true. It may not actually lead to the conclusion beyond a reasonable doubt. You only have to answer what has been asked (which is an assumption), not what you think is better to make the conclusion true.

Quarter Wit, Quarter Wisdom: And Now, Evading Formulas!

Quarter Wit, Quarter Wisdom: And Now, Evading Formulas!

Today, we again pay homage to the lazy bum within each one of us in our QWQW series. If you are wondering what we mean by ‘again’, check out our last two posts of the QWQW series. We have been discussing how to avoid calculations. Today let’s learn why it is advisable to avoid learning formulas too!

Quarter Wit, Quarter Wisdom: Evading Calculations Part II

Quarter Wit, Quarter Wisdom: Evading Calculations Part II

Last week we discussed how to solve equations with the variable in the denominator. We also said that the technique generally works for PS questions but you need to be careful while working on DS questions. Today, let’s look at the reason behind the caveat.

Quarter Wit, Quarter Wisdom: Evading Calculations!

Quarter Wit, Quarter Wisdom: Evading Calculations!

We have discussed before how GMAT is not a calculation intensive exam. Whenever you land on an equation which looks something like this: 60/(n – 5) – 60/n = 2, you probably think that we don’t know what we are talking about! You obviously need to cross multiply, make a quadratic and finally, solve the quadratic to get the value of n. Actually, you usually don’t need to do any of that for GMAT questions. You have an important leverage – the options. Even if the options don’t directly give you the values of n or n-5, you can use the knowledge that every GMAT question is do-able in 2 mins and that the numbers fit in beautifully well.

Quarter Wit, Quarter Wisdom: An Official Assumption Question

Quarter Wit, Quarter Wisdom: An Official Assumption Question

Today we will look at an OG question of critical reasoning (as promised last week). We will use the concept discussed last week – remember what an assumption is. An assumption is a missing necessary premise. It will bring in new information essential to the conclusion.