In this post, we are going to learn some tricks or strategies for being capable of calculating a square number mentally.

#### What is a square number?

A square number or a number raised to the power of 2, is a number multiplied by the same number.

In those cases the multiplication is simple, but if we want to calculate 62² the multiplication is more complicated. This is why we are going to look at two tricks for finding the square of numbers in a much simpler way.

#### Square of a number that ends in 5

The steps to follow are:

- We remove the units ones place digit from the number, that is to say, we remove the 5.
- We multiply the number that remains by the number that comes after this number when counting.
- We add the number 25 on to the end of the result of the previous multiplication.
- We already have the result of taking the square of that number.

**Let’s look at an example: 25²**

- We take the number 25 and remove the 5. So only the 2 remains.
- We multiply the 2 by the number that follows it when counting (so 3) following number:

#### 2 x 3 = 6

- After the 6 we add the number 25:

#### 625

- We have already arrived at the result of the operation:

#### 25² = 625

**Another example: 405²**

- We take the number 405 and remove the 5. We are left with 40.
- We multiply 40 by the number that follows it when counting (so 41) following number:

#### 40 x 41 = 1,640

- We add 25 on to the end of the number:

#### 164,025

- We have already arrived at the correct result:

#### 405²= 164,025

#### Square of a number close to 50

Let’s consider the numbers close to 50: those that are between 41 and 59. For these numbers you calculate their square in the following manner:

- We subtract 25 from the number. This number will be the first two digits of the final result.
- We find the difference between 50 and the number.
- We square that difference and the result will be the last two digits of the final result.

** Let’s look at an example: 47²**

- We subtract 25 from the number. These will be the first two digits of the number.

#### 47 – 25 = 22

- The difference between 50 and 47 is:

#### 50 – 47 = 3

- We square the number 3:

#### 3² = 9

The first two digits of the number are 22 and the last two digits are 09.

#### 47² = 2,209

**Let’s look at another example: 56²**

- We subtract 25 from the number:

#### 56 – 25 = 31

- We take the difference between the number and 50:

#### 56 – 50 = 6

- We square the previous number:

#### 6² = 36

Combining the first two digits and the last two digits we are left with:

#### 56² = 3,136

And that’s it for this week’s post. We hope that you have enjoyed this post and that we have taught you how calculate the square of a number in a simpler way.

If you want to learn much more math, try Smartick for free!

### Learn More:

- Tricks to Solve Combined Operations
- Learn 5 Tricks for Addition and Some Examples
- Learn and Practice How to Subtract or Add Fractions
- How to Solve a Problem Involving Dividing 2 Digit Numbers
- The Square of a Number and Exponents

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