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# Tricks to Master Math

If you are all bad with math - it's not entirely your fault.

We simply were not taught at school as needed, because mathematical tricks, with which any calculations become elementary, are easier to remember.

Multiplication of large numbers in the mind, How to learn the multiplication table by 9, The butterfly method for adding and subtracting fractions, Multiplying the number by 11 (by the example of the number 32), How to recall the Pi number, How to find a percentage of the number, How to find a fraction from an integer, Translation of degrees according to Fahrenheit in degrees Celsius, Fast squaring, Multiplication by 5, Multiplication by 11, Multiplication by 4, Multiply multiplication, Divide by 5, Subtraction of 1000

## Quick squaring

This technique will help quickly to square the two-digit number, which ends at 5. Multiply the first digit by itself + 1, and at the end add 25. That's it!

## Multiplication by 5

Divide the number by 2. If the result is an integer, assign 0 to the end. If not, do not pay attention to the comma and at the end add 5.

## Counting tips

If you need to leave 15% of the tip, there is an easy way to determine how much this is. Calculate 10% (divide the number by 10), and then add the resulting number to its half and get the answer.

## Complex multiplication

If you need to multiply large numbers, one of which is even, you can simply regroup them to get an answer.

## Division by 5

In fact, dividing large numbers by 5 is very simple. All you need is just multiply by 2 and move the comma.

## Subtraction of 1000

To perform a subtraction of 1000, you can use this simple rule: subtract 9 from all but the last digit, and subtract the last digit from 10.