This is so when numbers are multiplied by eleven.

For x 11, the process revolves round the fact that "any number" x 1 = "the same number".

Let me explain.

Y x 11 = Y x (10 + 1) = 10Y + Y.

**Example:**

25 x 11 = 25 x (10 + 1) =

**2**50 + 25 =

**2**75

Now, look carefully!

The final multiplied result of

**2**75 has its digit "

**2**" taken from the 10-th digit of the

*original*"

**2**5", and the digit 5 of the multiplied (product) result is taken from the 1-th digit of the original 2

**5**.

What then is in the centre digit of the multiplied result (2

**7**5)?

It is the maths addition of the 2 end digits of the original 25 , which is "2 + 5" = 7!

Got the picture?

This is due to the fact that the "x10" shifts the 25 left by one digit. Thus retaining the number 2 on its leftmost digit at the multiplied end product.

To summarise:

Multiplying 25 x 11 = a three digit number. This three digit number is obtained by inserting into the centre of the final product result, the addition of the two numbers 2 and 5 (the original 25). OK?

**New Example:**

32 x 11 ==>

3

**3**, (

**3**+ 2), 2 ==>

**3**52 (answer).

Maths is fun and interesting if you understand the underlining tricks !

For other exciting details about this topics, refer to

**this link**.

:-)

.

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