Math is one of the basic subjects at school. While incredible for some, Math can be a real nightmare for others.
If you are one of those who consider Math to be tedious, you’ll change your mind once you see how amazing these Math tricks are.
If you know your Math you will always be fun to be with and you’ll never feel bored at a lame party again, and what’s more you can also cheer up the crowd. Try them and you’ll see.
Here are 6 mind blowing math tricks:
1. Reading minds
Ask one of your friends to think of a number between 1 and 20. Let’s say the number he thought of is 8. Then ask him to add 5 to the number and multiply the sum by 3.In this case the result will be 39. After that ask your friend to subtract 15 from the result and he’ll get 24.
Then tell your friend that if he tells you the result you’ll tell him the number he thought of. He’ll say 24. Then you have to divide the result by 3 and tell your friend the result. Try to look as mysterious as you can in order to make it more interesting.
2. Multiplying by 11
It’s very easy to multiply any number by 11 if you know this little trick.
For example let’s take the number 43. Add the numbers 4 and 3 and you’ll get 7. Then put the number 7 between the numbers 4 and 3. And you’ll get the result 473. You can check on the calculator but you’ll still get the same result.
Now let’s extend the challenge and do the same with the number 78. Add the numbers 7 and 8 and you’ll get 15. But then don’t put the number 15 between the numbers 7 and 8, instead put the second digit, number 5, between the numbers 7 and 8 and add the first digit, number 1, to the number 7. You’ll get the result 858 which is the correct result.
3. Guessing the age
Let’s say that your friend is 21, but you don’t know that. Ask him to multiply his age by 5 and then add 8 to the result, after that multiply that result by 2.
Then he’ll have to subtract 6 by that number and multiply it by 10. Now ask him to tell you what he’s got. Then subtract 100 from this number and divide the result by 100. The number you get is the age of your friend.
4. Instant squares
As we all know a square is a product of a number multiplied by itself. For example 82 is the number you get when 8 is multiplied by 8, which is 64. That’s pretty easy if you know the multiplication table.
But what’s with the squares of two digit numbers? Well, those can be quite easy too if the second digit is 5.
Let’s take 65 for example. First you need to multiply 6 by 7, or the first number plus 1 (6+1). Then simply put 25 at the end of the sum and you’ll get a four digit number. In this particular case 4225 which is the square of 65.
See, it’s quite easy but keep in mind that this only works with numbers ending in 5.
5. Fibonacci sequence
The Fibonacci numbers also known as the Fibonacci sequence are characterized by the fact that every number after the first two is the sum of the two proceeding numbers.
So ask your friend to write down two numbers, the higher one on top of the lower one. Stay aside so your friend is sure that you’re not peeking. Now tell him to sum up the numbers and write the sum below.
Then ask him to sum up the last two numbers and to write the result. Let him continue until ten numbers are written down in a column. Then you come up and immediately write the sum of all the numbers. Your friend could check the result if he wants, but it’ll definitely be correct.
Imagine his astonishment seeing you as a genius who has just sum up a sequence of ten numbers in just a minute.
Here’s the secret. All you have to do is multiply the seventh number by 11 which you already know how to do.
The number you get is also the sum of all the ten numbers your friend wrote.
6. Guessing the result
And the last one is the coolest trick of all. This trick will definitely blow your friend’s minds.
Take out a sheet of paper and write down a six digit number. Ask your friend to write another six digit number below, preferably with different digits. Then you should write another number and then someone else writes another number below and then you need to write the last one.
Now ask someone to sum up all the five numbers. When the sum of the numbers is written down, you take out a piece of your pocket and what do you know, the same number is already written down on it.
“How did you do that?” –your friends would ask in disbelief. Well there’s an explanation for it, which of course doesn’t involve magic.
Here’s the secret. For example let’s take the following sequence of numbers:
Look at the second and the third number, where the second is written down by your friend and the third by you.
Summed up these two numbers have to equal 999999, so it means that you’d have to write a number which added up to the second one should equal 999999. The same has to happen with the last two numbers. So the sum of the last four numbers would equal 999999 multiplied by two that is 1999998.
Before the trick you have to choose a seven digit number which is bigger than 1999998 write it down on a piece of paper and put it in your pocket.
Don’t forget that the first number of the sheet should be the result of subtracting 1999998 from your seven digit number. So you must memorize it very well so the trick would work. If you are very careful and you don’t make any mistakes the sum of the five numbers would be equal to the sum you have in your pocket.
Cool, ha? Try these tricks and have fun with your friends. See I told you Math isn’t so boring after all.
A professional writer with over a decade of incessant writing skills. Her topics of interest and expertise range from health, nutrition and psychology.