Divisibility Rules

Given a number $x$, can you determine if it is divisible by a number say $y$ with out even performing the actual division. Divisibility rules are quite handy when you want to test for divisibility of numbers even before you can actual divide the number. For instance, to check if a number is divisible by 7, […]

Solving Absolute Value Equations

[latexpage] In this post we will see how to solve problems on absolute value(modulus) equations and inequalities. To understand the basics of absolute value click here – Absolute Value Solving absolute value problems of the type |f(x)| + g(x) = k How to find the value of x in absolute equations involving |f(x)| + g(x) […]

Remainders of Large Numbers using Fermat’s and Euler’s Theorem

To understand the basics of calculating remainders like the sum and product of remainders, concept of negative remainders etc click here – Remainders Basics In this post we will see how to find the remainders of large numbers using the remainder theorems – Fermat’s Little theorem and Euler’s theorem using the Euler’s Totient function. Fermat’s Little […]

Quickly Square Two, Three or Four digit numbers

In this post we will learn to mentally square two, three or four digits using an interesting trick in vedic maths. We will use the concept of duplex of numbers to quickly square two digit numbers. Lets first understand what is a duplex of a number. For a single digit number, say ‘a’ , Duplex of […]

Percentage problems involving two variables

In this post we will see how to deal with percentage problems involving two variables. Consider the two problems on percentage given below, If A x B = k, where A and B are variables and k is constant, then if A increases by 10%, what is the percentage change in B? If A’s salary […]

Percentage Increase and Decrease

Here we will explain how to solve problems on Percentage increase and decrease using the concept of Multiplication factor. The concept of Multiplication factor can be used for simplifying problems on Profit, Loss, Data Interpretation etc.

Using Chinese Remainder Theorem

A bag has certain number of pens. If you take out 3 pens at a time, 2 pens are left, if you take 4 pens, 1 pen is left and if you take 5 pens at a time, 3 pens are left in the bag. What is the smallest number of pens in the bag? […]

Least Common Multiple

In this post we explain the basics of Least Common Multiple(LCM). We will understand the techniques on how to find the LCM of two or more numbers. Under the “Problems on LCM” section we will solve some important aptitude problems on LCM. Understanding Least Common Multiple   Problems on LCM