It’s been one hell of a journey for last few months. During this period, I have had the privilege of teaching some of the brightest students from young to not so young.. The response from them has been truly humbling. I also, received a number of messages from students how … Continue reading

## RIP Shakuntala Devi

It’s a sad day for all of us here to know that Shakunthala Devi, the Human Calculator from India is no more.   For the entire generation of students who have been inspired to love Mathematics, it is such an unbearable loss.     Growing up as a … Continue reading

The best things in life don’t often come free. So, there is nothing like free lunches in this world right? The same is true with lot of news websites these days. There are a number of websites like New York Times, AutoSport where they classify the news articles as … Continue reading

## How to multiply any number by 101?

In this tutorial, we are going see an interesting class of numbers like 101, 203, 10001, 201 etc. Notice an important thing here. You have 2 different numbers (may be same or different) at the end and you have 1 or more zeros in between.   What is so … Continue reading

## How to obtain the squares of the numbers ending in 95?

This shortcut is really cool. Using this shortcut, you can obtain the squares of any number which ends in 95. For example, numbers such as 195, 295, 595 etc. Let’s say, we want to calculate the square of 295 i.e., 2952. The entire steps can be illustrated in … Continue reading

## How to obtain the squares of the number ending in 05?

This is an interesting find. While teaching students on obtaining the square of any number, I observed an amazing patterns in the squares of the number which ends with the digits 05 like 105, 205, 1105 etc.   You already know the shortcut, how to multiply any number ending … Continue reading

## How to find the day of a January 1st ?

This has to be an absolute classic of a shortcut that I came across  in the book “Secrets of Mental Maths”. Using this shortcut, you can find the day of January 1st of any year after 2000. Mind you this technique is only applicable for years after 2000. For … Continue reading

## HCF and LCM

Questions on HCF and LCM are the most common in the competitive examinations.  We have already studied HCF & LCM in our elementary schools.  Let’s recall from our memory.   Highest Common Factor (HCF)   Highest Common Factor (HCF) or Greatest Common Divisor (GCD) is the greatest number that divides … Continue reading

## Problems based on ages

Problems based on ages are probably the most frequently asked questions in the Competitive examinations. And believe me, it is also among the easiest of the questions, you would be attempting in the examinations. With the knowledge of solving linear equations, you can solve any problem related to ages. … Continue reading

## Divisibility Rules

So, how do we check if a number is divisible by another number (divisor). Do we have to divide the number to check if the reminder is 0 to conclude if the number is divisible by divisor? If the number or the divisor is a large number, maybe … Continue reading