Fast Math Multiplication

Is there an easy way to calculate? Yes, there is. 

Today,  I would like to share some easy Mathemathics calculation techniques.

With these fast mathematics techniques, even a small kid also can do a question that involves a long calculation in a few seconds. 

We all know that our mind always seeks to get maximum work done using minimum effort.

I am sure that everyone of us wish to solve a question by using the easiest and fastest way because it save time.

First technique

The first technique is fast multiplication that involve multiple 11.

Can you calculate   21432 x 11 = ___     in 6 seconds?

I am sure that most of us will use a harder way to solve it.

Actually, we can solve it by using an easier way as below:

The 1^st digit of the answer is the same as the 1^st digit of 21432, which is 2.

The 2^nd digit of the answer is the sum of the 1^st digit with the 2^nd digit of 21432, which is 2+1=3.

The 3^rd digit of the answer is the sum of the 2^nd digit with the 3^rd digit of 21432, which is 1+4=5.

The 4^th digit of the answer is the sum of the 3^rd digit and the 4^th digit of 21432, which is 4+3=7.

The 5^th digit of the answer is the sum of the 4^th digit and the 5^th digit of 21432, which is 3+2=5.

The 6^th digit of the answer is the same as the last digit of 21432, which is 2.

Therefore, 21432 x 11 = 235752.

Second Technique

The second technique is fast multiplication that involve multiple 12.

Now, let’s solve     1332 x 12 = _______

The 1^st digit of the answer is the same as the 1^st digit of 1332, which is 1.

The 2^nd digit of the answer is the sum of the double of the 1^st digit with the 2^nd digit of 1332, which is ( 2 x 1 ) + 3 = 2 + 3 = 5.

The 3^rd digit of the answer is the sum of the double of the 2^nd digit with the 3^rd digit of 1332, which is ( 2 x 3) + 3 = 6 + 3 = 9.

The 4^th digit of the answer is the sum of the double of the 3^rd digit with the 4^th digit of 1332, which is ( 2 x 3 ) + 2 = 6 + 2 = 8.

The 5^th digit of the answer is double of the last digit of 1332, which is 2 x 2 = 4.

Therefore, the answer for the question 1332 x 12 is 15984.

 

I found out that these techniques are very useful. Home tutor is my part time job and I teach Mathematics. I introduce these fast techniques to my students. I feel grateful when they can understand these techniques and can solve the question correctly in a nick of time.

With these fast calculation techniques, we can get the answer in a short time. 

Is it fun? Yes, it is.

Many people claimed that Mathematics is boring and hard to understand.

But for me,  I think it is fun and entertaining.

Hope you all enjoy it.

~Ewe Sin Hooi