## Posts

### Aptitude formulas pdf

After investing some time in the preparation, it's not uncommon to realize that it would be better if we make our own notes which we can refer while revising these topics before the exam. In order to make this procedure simple, I have come up with this post.
1) Ratios and proportions: If a certain amount N is divided among A, B in a ratio a:b then
A's share is a/(a+b) * N and B's share is b/(a+b) *N
If A:B = a:b and B:C = c:d then A:C = a*c : b*d
If A:B = p:q, B:C = r:s, C:D = t:u then
A:D = A/D = (A/B) * (B/C) * (C/D)
If a quantity is increased by a/b then the new content becomes (a+b)/b
If a quantity is decreased by a/b then the new content becomes (b-a)/b

To reduce your computations, it is always recommended to remember these values in terms of percentages
1/1 = 100 %
1/2 = 50 %
1/3 = 33.33 %
1/4 = 25 %
1/5 = 20 % 1/6 = 16.66 %
1/7 = 14.28 %       1/13 = 7.6%
1/8 = 12.25 %       1/12 = 8.33%
1/9 = 11.11 %       1/11 = 9.09%
1/10 = 10 %
Proportion is a number considered in compa…

### aptitude test free online

Preparing for any aptitude test without practicing or taking mock tests could be risky especially in this digital era it is not at all recommended to take a test without taking a few mock or practice test.  But how to take the mock tests for free without paying even a single penny? well, the purpose of this article is to help you with the best suitable sites to practice for your test.

There is a saying "promises are promises, Excuses are Excuses but only performance is the Reality" and this is what is applicable while selecting a good test among the various sites. many tests promise that they offer a great set of questions as well as experience but most of them end up with some excuses while only few will remain with a good performance and quality papers and our focus is on these sites.

List of websites that provide free aptitude tests and papers of many companies as well as tests: Geeksforgeeks: It is one of the best websites which provides standard questions on coding as w…

### Tricks and techniques to find square of a number with in seconds?

Solving aptitude and trying to do fast math?
you are here at the correct place then. this post enables you to solve square of a number within a few seconds when results are observed practically, the average time taken to find squares of 10 random numbers is 103 seconds.

Before going into the topic, let me tell my experience, it was a typical day in our college and that was a boring lecture and all the students were busy trying to listen the class, there begins the actual story my friend who is aiming to crack the CAT exam and get a seat in one of the reputed MBA school was doing some rough work at the end of his notes. he then told me the importance of fast math in the competitive exams and how it reduces the solving time from minutes to seconds in many cases. being curious about the fast math, I have searched a lot to find the squares of the numbers and found many techniques after watching youtube videos, referring some books, blogs... but it was a big question mark which one to beli…

### 5 Interesting facts about Digital sum and Digital roots

Have you ever gone through the topic called digital sum and surprised? Don't worry if you have not yet gone through because this post is exclusively for people like you. Solutions for these questions gets cleared after reading this post. What is Digital sum?How does digital sum help to save time?What is a Digital root? Digital sum: Digital sum can be defined as the sum of all the digits of a number. Digital root: The Digital root of a number can be obtained by finding digital sum repeatedly until you get a single digit.
Let A, B be two numbers. Digital root properties: Digital root(A*B) = Digital root( Digital root(A)*Digital root(B) )Digital root(A^2) = Digital root(Digital root(A)*Digita root(B))Digital root(A+B) = Digital root( Digital root(A)+Digital root(B) )Digital root(A-B) = Digital root( Digital root(A)-Digital root(B) )Digital root(10^x + A) = Digital root(A) How are these properties going to help you in saving your time? If you got a question to pick a square of a number fr…

### Ratios and proportions

Ratios and proportions is one of the most important topic in aptitude because of wide range of it's applications like ages, percentages, mixtures and allegations...
Ratio is a quantitative relation between two or more numbers which tells how many times one number is w.r.t other.

If a certain amount N is divided among A, B in a ratio a:b then
A's share is a/(a+b) * N and B's share is b/(a+b) *N
If A:B = a:b and B:C = c:d then A:C = a*c : b*d
If A:B = p:q, B:C = r:s, C:D = t:u then
A:D = A/D = (A/B) * (B/C) * (C/D)
If a quantity is increased by a/b then the new content becomes (a+b)/b
If a quantity is decreased by a/b then the new content becomes (b-a)/b

To reduce your computations, it is always recommended to remember these values in terms of percentages
1/1 = 100 %
1/2 = 50 %
1/3 = 33.33 %
1/4 = 25 %
1/5 = 20 % 1/6 = 16.66 %
1/7 = 14.28 %       1/13 = 7.6%
1/8 = 12.25 %       1/12 = 8.33%
1/9 = 11.11 %       1/11 = 9.09%
1/10 = 10 %
Proportion is a number considered in …

### prime numbers

Prime numbers in Mathematics have a great property that they are divisible ONLY by '1' and by itself.

Traditional method to check whether a given number is prime number or not:
Check for the divisibility test for each and every number from 1-number but that is the worst strategy to solve problems based on prime numbers in aptitude.

Moderate method suggested to check for the Divisibility test for each and every prime or odd number from 1 to √(number) and this reduced some complexity in solving these problems.
Even this method failed to minimize the computation and thus a great concept of Prime Series came into existence which generalized the form of a prime number.

Generalized form of Prime number:  6*K ± 1 (K is a natural number)
"Every prime number is in the form of 6*K ± 1 " but not every  6*K ± 1 is Prime number.
To prove the above statement,
We can define each and every integer as (6*k-3) :Divisible by 3
(6*k-2) :Divisible by 2
(6*k-1)
(6*k+0) :Divisible by 6
(6…

### Logarithm quantative aptitude question and answers

Logarithms have a wide range of applications in solving problems which are based not only on logarithms but also on the problems like finding the bigger number of 2^51 and 5^30. Logarithms also have many other applications which when used gives an immense sense of its usage.
What is a Logarithm?
A Logarithm is a quantity which represents the rise of it in terms of another number (base)
How it was derived, is there any formula to get logarithmic values?
Yes, there is a series called logarithmic series which will generate value of the logarithms

The main terms which one should be more familiar with before solving logarithmic problems are
Exponent: Power of a number.
Base: The number to reduce another number when log is applied.
Some Basic Logarithmic formula:
log ab = log a + log b
log a/b = log a - log b
log(a^b) = b*log(a)
logab = 1/logba
logbn = logen/logeb
log10n = logen/loge10 = logen *(0.43429448..)

Tool to find logarithm value of a number
Calculate

*******************************…

### Playing with factorials

Have you ever gone through factorial dependent questions in aptitude? Many problems which deal with factorials seems to be too complex and most of us may skip those questions even before a single try.so how can we stop these problems irritating or confusing us? well a few simple procedures to solve all such problems are given here
Before starting the procedures, let us learn about basics... Factorial(!): Product of an integer with all the integers below it. e.g: 4! = 4*3*2*1 The Highest power of a prime number 'P' (P is prime) in factorial of another number 'N' is
N/P + N /P^2 + N/P^3 + .....

### Problems on trains aptitude tricks

Voila, you are here!
Problems on trains in aptitude problems are not just to test your ability to solve the problems on trains and their properties but you can logically resolve many theories using this concept and this is one of the important part while learning aptitude.
Conversions:

A Kilometer/Hour = A(5//18) meter/second.A meter/second = A(18/5) Kilometer/Hour. Foundation: Time taken by a train of length 'l' units to cross a fixed point or pole is equal to the time taken by the train to travel 'l' units.Time taken by a train of length 'l' units to cross a  stationery object of length 'm' units units is equal to the time taken by the train to travel 'l+m' units.Suppose 2 trains are moving in the same direction with speeds U , V where U > V then their relative speed is U - V .

### mixtures and alligations problems

Alligation rule is used to determine the exact proportion to mix two ingredients of any price to obtain a mixture with estimated cost.

Mean price: Cost price of the mixture per unit.
suppose a container contains x units of liquid out of which y units are replaced then quantity of liquid after n such operations left in container would be x(1-y/x)^n

Alligation rule: Quantity of cheap ingredient(b) : Quantity of costly ingredient (a)= x2-x1 : x1-x0
point to remember:
cost price of mixture always lies between two costs.
Consider the graph Quantity v/s Cost , with this method one can solve problems with more ease A: Type of cheaper ingredient. B: Type of costly ingredient.
x0: cost of cheaper ingredient.
x1: cost of mixture.
x2: cost of costly ingredient.
Quantity of cheap ingredient : Quantity of costly ingredient = x2-x1 : x1-x0