|
I have this friend named
Arya, who's a mathematics wizard. He used to stun us all with his magic with numbers. Every Sunday we have a half-hour magic session from the Mathemagician
Arya.
This section is dedicated to my dear friend - Arya Bhatt. |
Some math-e-magic trick
I learnt from Arya, the trick for multiplying two 3-digit numbers in just few seconds. It just takes as much time to get the result by this method as it takes to get it from the calculator, provided you know your tables from 2 to 9 right. Check this section out and experiment with the magic of MATHEMATICS
Multiplying two 3-digit numbers can never be so simple. Try this out.
Lets take an example say - 297 x 843
Looks difficult? Not any more.
|
1. Tricks with numbers 2 and 5
|
Step 1
Write the numbers one below the other.
2 9 7
8 4 3
Step 2
Multiply the last digits of both the numbers and write the product at the units place. If there is nay number in the product in the tens place, carry it further. The operation of multiplication will look like 'I'
So in our example
2
2 9 7
8 4
3
----------------
1
|
|
|
|
|
|
|
Step 3
Now multiply the digit in the tens place of the first number with that in the units place of the second. Separately multiply the digit in the units place of the first number with that in the tens place of the second. The multiplication operation on the paper will look like 'X'. Now add the two products. Put the digit in the unit
place of this sum, in the tens place of our answer and carry on the digit in the tens place.
|
(9 * 3) + |
(4 * 7)+2 |
1 |
| |
(27 + |
28) + 2 |
|
| |
5 |
7 |
|
|
|
|
|
|
|
Step 4
This step can be best explained through the diagram. So look at the following operation carefully.
| 5 |
|
|
|
|
|
2 |
9 |
7 |
|
|
| 8 |
4 |
3 |
|
|
| |
|
|
7 |
1 |
| (2 * 3) |
+ (8 * 7) |
+ (9 *
4) + 5 |
7 |
1 |
| 6 |
+
56 |
36 +
5 |
7 |
1 |
| 1 |
0 |
3 |
7 |
1 |
|
|
|
|
|
What we do in this step is multiply the digit in the hundred's place of the first number with that in the units place of the second. Separately, multiply the digits in the ten's place of both the numbers. And further multiply the digit in the unit's place of the first number with that of the hundred's place of the second. Then we add all the 3 products together. The digit in the unit's place of the sum is then written in the hundred's place of our answer. And those in the hundred's and ten's place are carried further. The operation here looks like 'I' through 'X' -
Step 5
Now multiply the digit in the tens place of the first number with that in the hundred's place of the second. Separately multiply the digit in the hundred's place of the first number with that in the tens place of the second. The multiplication operation on the paper will look like X again, but now on other side. Now add the two products. Put the digit in the units place of this sum, in the thousand's place of our answer and carry on the digit in the tens place.
| 2 |
9 |
7 |
|
|
|
| 8 |
4 |
3 |
|
|
|
| (2 * 4) + |
(8 * 9) + |
10 |
3 |
7 |
1 |
| 8
+ |
72
+ |
10 |
3 |
7 |
1 |
| 9 |
0 |
3 |
7 |
1 |
| |
|
Step 6
Now, multiply the first digits of both the numbers. Add to this product, the number that has been carried on through the previous step and write the sum at the ten thousand's place. If there is any number in the product in the tens place, write it in the lakh's place. The operation of multiplication will look like 'I'
| 9 |
|
|
|
|
|
|
|
| |
2 |
9 |
7 |
|
|
|
|
| |
8 |
4 |
3 |
|
|
|
|
| |
(2 * 8) |
+ 9 |
|
0 |
3 |
7 |
1 |
| |
16 |
+ 9 |
|
0 |
3 |
7 |
1 |
| |
2 |
5 |
|
0 |
3 |
7 |
1 |
|
|
|
= 250371
And that's our final answer
297 x 843 = 250371
Isn't that simple? You'll say no. But that's because you have just read this, have you tried it with other numbers as yet? Do it yourself and then get back to us. If you find it difficult, Arya will help you out.
By following the same pattern of operations shown above, you can multiply any number of digits. Isn't that wonderful?
|
Swami's trivia
This trick actually comes from the swamis of ancient times. This was the process they used to do maximum calculations. They could do any mathematical operation on any number with any number of digits in it in mind. This ancient Indian process of mathematics is called - Vedic mathematics.
|