## How to Calculate Faster Than a Calculator

When you need to crunch numbers quickly—and I mean *really* quickly—there's a cool method you can use to multiply 2 numbers together in just a few seconds.

This is a great for impressing your math teacher or peers, or just a cool party trick (depending on your crowd).

For the first example, let's calculate the following:

Start by taking the first digit of the first number (2 for 24) and multiplying that by the number directly ahead of it, which will give you the first digit(s) of the answer.

24 x 26 =

so....

2 (first digit in first number) x 3 (one digit higher) = 6

**6** is our first digit in the answer.

Now take the second digit of the first number (4 for 24) and multiple that by the second digit of the second number (6 for 26), which will give you the remaining digits of the answer.

24 x 26 = 6__

so...

4 (second digit in first number) x 6 (second digit in second number) = 24

**2** and **4** are the the last digits of the answer.

So, 24 x 29 = **624**

Voila!! You're done. But wait, there's more.

## A Few Restrictions

If you thought this method was too good to be true, well, you're right. There are a few restrictions, or caveats, that must be adhered to:

- the first digits of both numbers must be the same
- the last digit of both numbers must equal 10

If you look at the example above, the first digit in each number (24, 26) is **2**, and the last digits in each (4, 6) equals **10**. Let's do a few more examples to hit this point home.

**37 x 33**

3 (first digit in first number) x 4 (one digit higher) = 12

**1** and **2** are our first digits in the answer.

7 (second digit in first number) x 3 (second digit in second number) = 21

**2** and **1** are the the last digits of the answer.

So, 37 x 33 = **1221**

**122 x 128**

12 (first digits in first number) x 13 (one digit higher) = 156

**1**, **5**, and **6** are our first digits in the answer.

2 (second digit in first number) x 8 (second digit in second number) = 16

**1** and **6** are the the last digits of the answer.

So, 122 x 128 = **15616**

For a more visual guide, check out the video below from Roger73026:

## 31 Comments

NOWAY

try with : 10 X 10 ???

84 X 88 ???

the last digits have to equal 10

ok

wow

well to solve the theory's problem... you can do it as (15-5)(15-5)=(15X15)-(15X5)-(15X5)-(5)^2 and then use the relation in 15X15... that's a general solution to have last digits adding to 10 with calibrating them to 5, anyone has a much shorter faster solution?

yea watch the whole video it has 2 meet 2 criterea... the first digit on the first number has to be the same as the first digit on the second.. and the 2 second digits have to add to 10... whcih all in all kinda makes this treick useless

Very good!

ok!!!!!!!!!!!!!!!!not too

good

well if ur smart enough to realize that then i guess you dont need this tip then do u? theres always exceptions to the rules; "i before e except after c?" that seems kinda weird doesn't it?

It has its limits Just like finding out the answer to any number multiplied by nine between one and nine. Where you take the number before the number you're trying to multiply with nine then find out what number added to it will equal nine then put the two numbers together and that is your answer. An example is 9 * 7 = 63 The 6 from 63 comes before the 7 from 9 * 7 and 3 added to the 6 will equal 9.

it kink of sucks because it would be a coincidence to run in to such a math question

yah you can teach this to children for trick purposes

try this:condition :two no. are of even dist.

ex:37*33 mid value =35

sq. 35 = 1225

37*33 = sq.35-dist b/w ywo digit i.e.4 = 1221

2 much of a coincidence needed 2 b of any use

very good

pretty cool!

its good to know some tricks

=)

pretty cool

Never thought i'd say this to a guy, but. I love ya man!

Very smart

THIS RULE IS JUST CRAP. IT DOESNT WORK

26 x26

46 x 47

98 x 97

12x19

Please remove this video else you may lend someone in trouble

Great job

hello, can i get any soft ware for this, like abacus solutions

hello can i get maths trick for download like this

not much useful

how to get by this 14

15,1418

cool~ tks a lot :D

very very cool!!!!!!!!!!!!!!!!!!!

smart and when I did it it didn't work!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

very very intersesting and learning

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