The weird number trick

Keep scrolling down slowly... Just keep saying this (in your head, "five five five, six six six".: 555 666 555 666 555 666 555 666 555 666 555 666 555 666555 666555 666555 666555 666555 666555 666555 666555 666555 666555 666555 666555 666555 666555 666 555 666555 666555 666555 666555 666 555 666 555 666 now... THINK OF A NUMBER!!!!!!!!!!!!!!!! You thought of 76 didn't you?

Awesome Mind Trick

This little Jedi mind trick is kinda freaky, till you think about it a little while. Then it's even more weird. Just follow the instructions below:
DON'T scroll down too fast, do it slowly and follow the instructions below exactly, do the math in your head as fast as you can. It may help to say the answers aloud quietly.
FOLLOW these instructions one at a time and as QUICKLY as you can!












What is:


* 2+2?
* 4+4?
* 8+8?
* 16+16?













Quick! Pick a number between 12 and 5.
























Got it?


The number you picked was 7.







Ready for another?
Just follow these instructions, and answer the questions one at a time and as quickly as you can! Don't advance until you've done each of them. Now, ARROW down, but not too fast, you might miss something.........


What is:


* 1+5
* 2+4
* 3+3
* 4+2
* 5+1













Now repeat saying the number 6 to yourself as fast as you can for 10 seconds. Then scroll down.
























QUICK!!! THINK OF A VEGETABLE! Then arrow down.
























You're thinking of a carrot.
If not....
you're among the 2% of the population whose minds are warped enough to think of something else. 98% of people will answer 'carrot' when given this exercise.

One more added::::

Think a number quickly between 50 and 100 and it must have even and disticnt digits....
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I hope U thought of 68...

Math Magic/Tricks [VERY INTERESTING]

Trick 1: Number below 10
Step1: Think of a number below 10.
Step2: Double the number you have thought.
Step3: Add 6 with the getting result.
Step4: Half the answer, that is divide it by 2.
Step5: Take away the number you have thought from the answer, that is, subtract the answer from the number you have thought.
Answer: 3


Trick 2: Any Number
Step1: Think of any number.
Step2: Subtract the number you have thought with 1.
Step3: Multiply the result with 3.
Step4: Add 12 with the result.
Step5: Divide the answer by 3.
Step6: Add 5 with the answer.
Step7: Take away the number you have thought from the answer, that is, subtract the answer from the number you have thought.
Answer: 8


Trick 3: Any Number
Step1: Think of any number.
Step2: Multiply the number you have thought with 3.
Step3: Add 45 with the result.
Step4: Double the result.
Step5: Divide the answer by 6.
Step6: Take away the number you have thought from the answer, that is, subtract the answer from the number you have thought.
Answer: 15


Trick 4: Same 3 Digit Number
Step1: Think of any 3 digit number, but each of the digits must be the same as. Ex: 333, 666.
Step2: Add up the digits.
Step3: Divide the 3 digit number with the digits added up.
Answer: 37


Trick 5: 2 Single Digit Numbers
Step1: Think of 2 single digit numbers.
Step2: Take any one of the number among them and double it.
Step3: Add 5 with the result.
Step4: Multiply the result with 5.
Step5: Add the second number to the answer.
Step6: Subtract the answer with 4.
Step7: Subtract the answer again with 21.
Answer: 2 Single Digit Numbers.


Trick 6: 1, 2, 4, 5, 7, 8
Step1: Choose a number from 1 to 6.
Step2: Multiply the number with 9.
Step3: Multiply the result with 111.
Step4: Multiply the result by 1001.
Step5: Divide the answer by 7.
Answer: All the above numbers will be present.


Trick 7: 1089
Step1: Think of a 3 digit number.
Step2: Arrange the number in descending order.
Step3: Reverse the number and subtract it with the result.
Step4: Remember it and reverse the answer mentally.
Step5: Add it with the result, you have got.
Answer: 1089


Trick 8: x7x11x13
Step1: Think of a 3 digit number.
Step2: Multiply it with x7x11x13.
Ex: Number: 456, Answer: 456456


Trick 9: x3x7x13x37
Step1: Think of a 2 digit number.
Step2: Multiply it with x3x7x13x37.
Ex: Number: 45, Answer: 454545


Trick 10: 9091
Step1: Think of a 5 digit number.
Step2: Multiply it with 11.
Step3: Multiply it with 9091.
Ex: Number: 12345, Answer: 1234512345

9 Great Mental Math Tricks

1. Multiplying by 9, or 99, or 999
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Multiply

ing by 9 is really multiplying by 10-1.

So, 9×9 is just 9x(10-1) which is 9×10-9 which is 90-9 or 81.

Let’s try a harder example: 46×9 = 46×10-46 = 460-46 = 414.

One more example: 68×9 = 680-68 = 612.

To multiply by 99, you multiply by 100-1.

So, 46×99 = 46x(100-1) = 4600-46 = 4554.

Multiplying by 999 is similar to multiplying by 9 and by 99.

38×999 = 38x(1000-1) = 38000-38 = 37962.
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2. Multiplying by 11
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To multiply a number by 11 you add pairs of numbers next to each other, except for the numbers on the edges.

Let me illustrate:

To multiply 436 by 11 go from right to left.

First write down the 6 then add 6 to its neighbor on the left, 3, to get 9.

Write down 9 to the left of 6.

Then add 4 to 3 to get 7. Write down 7.

Then, write down the leftmost digit, 4.

So, 436×11 = is 4796.

Let’s do another example: 3254×11.

The answer comes from these sums and edge numbers: (3)(3+2)(2+5)(5+4)(4) = 35794.

One more example, this one involving carrying: 4657×11.

Write down the sums and edge numbers: (4)(4+6)(6+5)(5+7)(7).

Going from right to left we write down 7.

Then we notice that 5+7=12.

So we write down 2 and carry the 1.

6+5 = 11, plus the 1 we carried = 12.

So, we write down the 2 and carry the 1.

4+6 = 10, plus the 1 we carried = 11.

So, we write down the 1 and carry the 1.

To the leftmost digit, 4, we add the 1 we carried.

So, 4657×11 = 51227 .

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3. Multiplying by 5, 25, or 125
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Multiplying by 5 is just multiplying by 10 and then dividing by 2. Note: To multiply by 10 just add a 0 to the end of the number.

12×5 = (12×10)/2 = 120/2 = 60.

Another example: 64×5 = 640/2 = 320.

And, 4286×5 = 42860/2 = 21430.

To multiply by 25 you multiply by 100 (just add two 0’s to the end of the number) then divide by 4, since 100 = 25×4. Note: to divide by 4 your can just divide by 2 twice, since 2×2 = 4.

64×25 = 6400/4 = 3200/2 = 1600.

58×25 = 5800/4 = 2900/2 = 1450.

To multiply by 125, you multipy by 1000 then divide by 8 since 8×125 = 1000. Notice that 8 = 2×2x2. So, to divide by 1000 add three 0’s to the number and divide by 2 three times.

32×125 = 32000/8 = 16000/4 = 8000/2 = 4000.

48×125 = 48000/8 = 24000/4 = 12000/2 = 6000.

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4. Multiplying together two numbers that differ by a small even number
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This trick only works if you’ve memorized or can quickly calculate the squares of numbers. If you’re able to memorize some squares and use the tricks described later for some kinds of numbers you’ll be able to quickly multiply together many pairs of numbers that differ by 2, or 4, or 6.

Let’s say you want to calculate 12×14.

When two numbers differ by two their product is always the square of the number in between them minus 1.

12×14 = (13×13)-1 = 168.

16×18 = (17×17)-1 = 288.

99×101 = (100×100)-1 = 10000-1 = 9999

If two numbers differ by 4 then their product is the square of the number in the middle (the average of the two numbers) minus 4.

11×15 = (13×13)-4 = 169-4 = 165.

13×17 = (15×15)-4 = 225-4 = 221.

If the two numbers differ by 6 then their product is the square of their average minus 9.

12×18 = (15×15)-9 = 216.

17×23 = (20×20)-9 = 391.

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5. Squaring 2-digit numbers that end in 5
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If a number ends in 5 then its square always ends in 25. To get the rest of the product take the left digit and multiply it by one more than itself.

35×35 ends in 25. We get the rest of the product by multiplying 3 by one more than 3. So, 3×4 = 12 and that’s the rest of the product. Thus, 35×35 = 1225.

To calculate 65×65, notice that 6×7 = 42 and write down 4225 as the answer.

85×85: Calculate 8×9 = 72 and write down 7225.

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6. Multiplying together 2-digit numbers where the first digits are the same and the last digits sum to 10
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Let’s say you want to multiply 42 by 48. You notice that the first digit is 4 in both cases. You also notice that the other digits, 2 and 8, sum to 10. You can then use this trick: multiply the first digit by one more than itself to get the first part of the answer and multiply the last digits together to get the second (right) part of the answer.

An illustration is in order:

To calculate 42×48: Multiply 4 by 4+1. So, 4×5 = 20. Write down 20.

Multiply together the last digits: 2×8 = 16. Write down 16.

The product of 42 and 48 is thus 2016.

Notice that for this particular example you could also have noticed that 42 and 48 differ by 6 and have applied technique number 4.

Another example: 64×66. 6×7 = 42. 4×6 = 24. The product is 4224.

A final example: 86×84. 8×9 = 72. 6×4 = 24. The product is 7224

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7. Squaring other 2-digit numbers
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Let’

s say you want to square 58. Square each digit and write a partial answer. 5×5 = 25. 8×8 = 64. Write down 2564 to start. Then, multiply the two digits of the number you’re squaring together, 5×8=40.

Double this product: 40×2=80, then add a 0 to it, getting 800.

Add 800 to 2564 to get 3364.

This is pretty complicated so let’s do more examples.

32×32. The first part of the answer comes from squaring 3 and 2.

3×3=9. 2×2 = 4. Write down 0904. Notice the extra zeros. It’s important that every square in the partial product have two digits.

Multiply the digits, 2 and 3, together and double the whole thing. 2×3x2 = 12.

Add a zero to get 120. Add 120 to the partial product, 0904, and we get 1024.

56×56. The partial product comes from 5×5 and 6×6. Write down 2536.

5×6x2 = 60. Add a zero to get 600.

56×56 = 2536+600 = 3136.

One more example: 67×67. Write down 3649 as the partial product.

6×7x2 = 42×2 = 84. Add a zero to get 840.

67×67=3649+840 = 4489.
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8. Multiplying by doubling and halving
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Th

ere are cases when you’re multiplying two numbers together and one of the numbers is even. In this case you can divide that number by two and multiply the other number by 2. You can do this over and over until you get to multiplication this is easy for you to do.

Let’s say you want to multiply 14 by 16. You can do this:

14×16 = 28×8 = 56×4 = 112×2 = 224.

Another example: 12×15 = 6×30 = 6×3 with a 0 at the end so it’s 180.

48×17 = 24×34 = 12×68 = 6×136 = 3×272 = 816. (Being able to calculate that 3×27 = 81 in your head is very helpful for this problem.)

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9. Multiplying by a power of 2
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To multiply a number by 2, 4, 8, 16, 32, or some other power of 2 just keep doubling the product as many times as necessary. If you want to multiply by 16 then double the number 4 times since 16 = 2×2x2×2.

15×16: 15×2 = 30. 30×2 = 60. 60×2 = 120. 120×2 = 240.
23×8: 23×2 = 46. 46×2 = 92. 92×2 = 184.
54×8: 54×2 = 108. 108×2 = 216. 216×2 = 432.

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