# Pipes and Cisterns (Concepts, Properties and CAT Questions)

June 21st, 2020 by

A pipe is connected to a tank or cistern. It is used to fill or empty the tank; accordingly, it is called an inlet or an outlet. Inlet: A pipe which is connected to fill a tank is known as an inlet. Outlet: A pipe which is connected to empty a tank is known as an outlet. Problems on pipes and cisterns are similar to problems on time and work. In pipes and cistern problems, the amount of work done is the part of the tank of filled or emptied. And, the time taken to do a piece of work is the time take to fill or empty a tank completely or to a desired level. Pipes and Cisterns Po

# How to Find Number of Trailing Zeros in a Factorial or Product

June 12th, 2020 by

In this Number of trailing Zeros blog post, We would like to cover these two ideas: Number of trailing zeroes in a Product or Expression Number of trailing zeroes in a factorial (n!) But before I begin, let us first try to understand what exactly are ‘trailing zeroes’. It is nothing else but the number of zeroes at the end. I do not want to sound pedantic but on many occasions when you see a question which asks about, “What is the number of zeroes in ___” it is incorrect, because it should actually say – “What is the number of trailing zeroes?” or “What is the

# Clocks – Concepts and Questions with Solutions for CAT Exam

May 30th, 2020 by

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

# How to find Rank of a Word in Dictionary (With Repetition and Without Repetition)

May 27th, 2020 by

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

# Permutation and Combination – Fundamental Principle of Counting

May 26th, 2020 by

For this series of articles, I am assuming CAT 2021 would be the first time you would be attempting CAT, which essentially implies that you are not well versed with the basic ideas behind the Quantitative Aptitude portion. In the latter half of the year, I would move to slightly more advanced topics as by then, you would also have moved to the advanced stage of preparation. Best Online Coaching for CAT 2021 I have often seen students struggle with the topic – ‘Permutation & Combination’. As a matter of fact, I have even seen some faculties shy away from conducting those cl

# Permutation and Combination – Distribution of Objects

May 21st, 2020 by

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

# Time Speed Distance – Motion of Two Bodies in a Straight Line

May 10th, 2020 by

There are some topics in Quantitative Aptitude, like Permutation & Combination,  where you can easily find out the answer and the answer you calculate is there in the options but it turns out to be wrong. And then there are some topics in which you read the question, understand it but cannot even begin solving it. You get stuck at the first step and you have no idea about how to even approach the question. The irritating fact is that you understood the question properly. It happens very frequently with questions on Time Speed & Distance (TSD). I have always been a big advocate of

# Ratio and Proportion – Concepts, Properties, and CAT Questions

May 7th, 2020 by

Ratio and Proportions is one of the easiest concepts in CAT. It is just an extension of high school mathematics. Questions from this concept are mostly asked in conjunction with other concepts like similar triangles, mixtures and allegations. Hence fundamentals of this concept are important not just from a stand-alone perspective, but also to answer questions from other concepts 1.  Ratio (Concepts and Properties) Many a times we compare two data values of the same type. One way to do this is to find out the difference (a-b). Other method of comparison could be by division or finding ou

# Factorial Concepts for CAT – Rightmost digit, Ending Zeroes, Power of a Prime

April 29th, 2020 by

We all know what factorials (n!) are. They look friendly and helpful but looks can be deceiving, as many quant problems have taught us. Probably it is because that Factorials are simple looking creatures, most students prefer attempting questions based on them rather than on Permutation & Combination or Probability. I will cover P&C and Probability at a later date but in today’s post I would like to discuss some fundas related to factorials, which as a matter of fact form the basis of a large number of P&C and Probability problems.   Some of the factorials that mig