Easy Math Trick YOU MUST LEARN!

Quick Addition Trick for Multiples of 11:

To quickly add multiples of 11, take the sum of the two digits in the number and place it in the middle. For example:

11 x 3 = 33 (1 + 1 = 2, so place 2 in the middle)

11 x 6 = 66 (1 + 1 = 2, so place 2 in the middle)

11 x 9 = 99 (1 + 1 = 2, so place 2 in the middle)

This works for larger numbers as well:

11 x 23 = 253 (2 + 3 = 5, so place 5 in the middle)

11 x 47 = 517 (4 + 7 = 11, so place 1 in the middle and carry over the 1)

It's a handy trick for mental calculations involving multiples of 11!

Here is another trick which may come in handy:

Certainly! Here's a trick related to the number 9:

Quick Multiplication Trick for 9:

To quickly multiply a number by 9, use this simple method:

Choose a number to multiply by 9.

Subtract 1 from the chosen number to get the first part of the answer.

The second part is what, when added to the first part, equals 9.

For example:

9 × 4

9 × 4: Subtract 1 from 4 (4 - 1 = 3), so the first part is 3. What when added to 3 equals 9? The answer is 6 (3 + 6 = 9). So,

9 × 4 = 36

9 × 7

9×7: Subtract 1 from 7 (7 - 1 = 6), so the first part is 6. What when added to 6 equals 9? The answer is 3 (6 + 3 = 9). So,

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