maths magic

http://www.mirror.co.uk/news/weird-news/amaze-your-friends-with-these-fantastic-maths-1593633

Maths Magic

Twos, threes & fives

Think of a number. Add 4, then multiply the result by 4. Subtract 8, then divide the result by 4. Finally take away your original secret number. The answer is 2.

Think of another number.

Double it. Add 9. Subtract 3. Divide by 2. Subtract your original number. The answer is 3.

Think of any three-digit number.

Add 7. Multiply by 2.

Subtract 4, then divide the result by 2.

Subtract it from the original number you thought of.

The answer is 5.

Ninety nine

Write down any two different numbers from 1 to 9. Then reverse the two numbers.

You should have two two-digit numbers.

Subtract the smaller number from the larger one.

Take the result, reverse the digits, and add that number to the one you got when you subtracted.

The answer is 99.

For example: 72 reverses to make 27.

Subtract the smaller (27) from the larger (72): 45.

Reverse these digits to make 54.

Add this to the previous number.

The answer is 99.