MATH TRICKS THAT WILL BLOW YOUR MIND

1) Six Digits Become Three
Take any three-digit number and write it twice to make a six digit number. Examples include 371371 or 552552.
Divide the number by 7.
Divide it by 11.
Divide it by 13. (The order in which you do the division is unimportant.)
The answer is the three digit number

Examples: 371371 gives you 371 or 552552 gives you 552.

A related trick is to take any three-digit number.
Multiply it by 7, 11, and 13.
The result will be a six digit number that repeats the three-digit number.

Example: 456 becomes 456456.

2)Multiplying by 6
If you multiply 6 by an even number, the answer will end with the same digit. The number in the tens place will be half of the number in the ones place.

Example: 6 x 4 = 24

3)Memorizing Pi
To remember the first seven digits of pi, count the number of letters in each word of the sentence:

"How I wish I could calculate pi."

This gives 3.141592