2. To multiply any two digit number by 11:

• 1 For this example we will use 43.
  
• 2 Separate the two digits in your mind (4__3).
  
• 3 Notice the hole between them!
  
• 4 Add the 5 and the 4 together (4+3=7)
• 5 Put the resulting 9 in the hole 473. That's it! 11 x 43=473
  

Note: If the addition result in the number greater than 9 then only unit place digit should be placed at middle. And tens place digit will be added to left most digit.

See Example:-

• Lets calculate 11x74
  
• We have now(7__4)
  
• After adding we got(7+4=11)
  
• Put 1 in the middle and carry other 1 to add with 7.(7+1=8)
  

Therefore the result comes out to be 814.

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3. Square a 2 Digit Number Ending in 5

For example we will use 45

• 1 Take the "tens" part of the number (the 4 and add 1)=5
  
• 2 Multiply the original "tens" part of the number by the new number (4x5=20)
• 3 Take the result and put 25 behind it.
  

Result the answer 2025.

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4. Multiply By 5

To quickly multiply by 5, divide the number by two and then multiply it by 10. This can be easily done quickly in your mind.

For Example:

• 1. Multiply 5 with 25
• 2. Divide 25 by 2 =12.5
• 3. 12.5 X10 =125
  

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5. Multiply by 9(Learn the table of 9 for children)

To multiply any number between 1 and 9 by 9 hold both hands in front of your face.

Drop the finger that corresponds to the number you are multiplying

For Example:

• 9×4 – drop your fourth finger – count the fingers before the dropped finger
  
• (in the case of 9×4 it is 3) then count the numbers after (in this case 6).
• The answer is 36.

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6. Dividing by 5

Dividing a large number by five is actually very simple. All you do is multiply by 2 and move the decimal point

For Example: 520 / 5

• Step1: 520 * 2 = 1040
  
• Step2: Move the decimal: 104.0 or just 104
  
• Therefore the answer is: 104

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7. This is the trick exclusively applicable to the multiplications of 2 numbers whose digits at unit's place add up to 10 as well as whose digits at tenth's place are same.

Both of these conditions should be satisfied.

For Example:

• In product of 73 & 77, digit at tenth's place is same i.e 8 & sum of 3 & 7 is 10. Now, follow the rules--  
• Firstly, find product of digits at unit's places i.e. here 3 * 7=21.
• Secondly, multiply tenth's place digit by next consecutive number i.e. here 7 * 8=56
  
• Now your answer is the outcome in second step i.e.56 followed by outcome in first step i.e.21
  
• Hence, your answer is 5621.

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