CAT

The common admission test or more popularly known CAT exam is in less than a month’s time from now. CAT happens to be an extremely important incident in a CAT aspirant’s life, one of those events that can change the course of ones life completely for the better if successfully cracked. This is the reason a particular person remains under immense bit of pressure through out the entire preparatory process and most importantly on the CAT day. To add to the pressure element the Indian Institute Of Managements...

Founded in 1983 in Gandhinagar in Gujarat, the Entrepreneurship Development Institute of India has been making conspicuous impacts in the field of making managers out of student. Not to look for job but to generate employment is the mantra of the institute. Thinking like an Entrepreneur and benefiting the society by generating employment is what is chiefly taught out there.

The institute has successfully broken the myths that entrepreneurs cannot be made but only born. The conspicuous...

I would teach you how you can multiply mentally for numbers from 11 to 19 without using any paper.

So lets start with a sample first.

Lets multiply 17x19

First you have to put the larger number front. i.e. 19x17 is what we would do.
First Add 19+7 i.e. we get 26.
Now multiply it with 10 i.e. it becomes 260.
Now multiply the units digit of both the numbers. i.e. 9x7 = 63.
Add both and thats your answer i.e. 260+63 = 323.

...

To quickly multiply by 5, divide the number in two and then multiply it by 10. This can be done quickly in your head.

How it works.

We can write 5 as 1/2x10

So now lets say we would like to multiply 28 and 5 and so using the above formula we can

First half 28 i.e. 14
Now multiplying it to 10 gives 140 and so answer is 140.

The same thing can be applied to 50 which is half of 100 i.e. 1/2x100

Generalizing the above...