Cyclicity of Remainders In this post I would like to discuss some of the really fundamental ideas that can be used to solve questions based on remainders. If you have just started your preparation for CAT Exam, you might find this article helpful. First of all, What I am trying to say above is that if you divide a^n by d, the remainder can be any value from 0 to d-1. Not only that, if you keep on increasing the value of ‘n’, you would notice that the remainders are cyclical in nature. What I am trying to say is that the pattern of remainders would repeat. Let me try to

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In the previous post we discussed lines, triangles, parallelograms, trapeziums, polygons etc. Now, we will discuss other expanses of geometry which are vital as, the questions on these topics are asked repeatedly in CAT. Let us look at few of the fundas / formulae on these topics that are often neglected by students and can fetch some crucial marks in the exam. Funda 1: Angle made by Secants       2 .   In both these cases, PA * PB = PC * PD   Funda 2: Common Tangents     eg: Note: The two centers

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I got a lot of feedback via emails and texts that people are looking for a post on geometry. I have been avoiding it for sometime because of two main reasons: a)      It is not one of my strong areas. b)      It takes a lot of time to draw the diagrams that are sometimes required to explain the fundas. The questions on geometry are the trickiest and consumes the maximum amount of time as compared to the questions on other topics in Quantitative aptitude that is why, I have compiled a list of fundas that you might find helpful in solving CAT level questions. I am splittin

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A very common type of question that gets asked in various banking and management entrance exams is based upon the concept of finding out the rank of a word. In this post, I will like to discuss the concept behind the same. Let us look at the two types. Rank of a word - without repetition of letters Suppose that you are given a word in which none of the letters are repeated and you asked to find out the rank of the word in a dictionary. For example, if the word which was given to you was CAT, it will be very easy to find out its rank. You will write down all possible combinations of

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While most students are comfortable with the concept of HCF (Highest Common Factor) and LCM (Lowest Common Multiple), they somehow fail to apply it when required. Sometimes, they do not even realise that it needs to be applied. I sometimes feel sad when students ask me, “Sir, when to apply HCF and when to apply LCM?”. This question is a symbol of everything that is wrong with rote learning. HCF and LCM are concepts that students start learning as early as the 5th class in school (may be even earlier in some cases). The problem occurs because a few of them forget how the concepts need t

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Questions on clocks (or even calendars) are not really frequent in CAT these days. They used to be really popular few years ago. Having said that, it is always better to understand some of the basic principles and the types of problems that get asked. They might come in handy in case of other exams like CMAT, MAT, SNAP, etc. Clock problems can be broadly classified in two categories: a)      Problems on angles b)      Problems on incorrect clocks Problems on angles Before we actually start solving problems on angles, we need to get couple of basic facts clear: Sp

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As an astute man Mr. Gump once said, “Life is like a box of chocolates. You never know what you going to get.” The Permutations and Combinations that life presents us daily is baffling and probably it is because of that inherent fear of choices and cases we get intimidated by such questions in the exam. I understand that Permutation and Combination is one of the dreaded topics but I hope that once you understand the fundas given below, your fear will reduce. Permutation and Combination Funda 1: De-arrangement If ‘n’ distinct items are arranged in a row, then the number of way

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I guess my first fascination with problems of Time, Speed and Distance began when I first saw Henna. An important part of the story line  if you can call it that, saw Rishi Kapoor floating from India to Pakistan without drowning. I remember arguing with my friends that if could float for that long – he could swim back to India as well. My friends nullified the argument by saying: Speed River > Speed Rishi Kapoor I know that the reference is a little dated for most readers of this post, but Zeba Bhaktiyar made me look beyond reason. In this post we will discuss some of the ideas that

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Figuring out the last digit is the same as figuring out the remainder of a number when divided by 10, but I guess you already know that. Figuring out the last two digits is the same as figuring out the remainder of a number when divided by 100. However, if you wish to figure the remainder when the divisor is not 10 or 100, I suggest you read on. Funda 1 of Remainders:  Basic idea of remainders can be used to solve complicated problems.     There is nothing special or unique about this idea. At first glance it seems like something really obvious. But it is it

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The concepts of Set Theory are applicable not only in Quant / DI / LR but they can be used to solve syllogism questions as well. Let us first understand the basics of the Venn Diagram before we move on to the concept of maximum and minimum. A large number of students get confused in this so I have listed out each area separately. A venn diagram is used to visually represent the relationship between various sets. What do each of the areas in the figure represent? I – only A; II – A and B but not C; III – Only B; IV – A and C but not B; V – A and B and

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