Short Cut

*Any number multiply by 11

E.g) 563*11=563=(10+1)=5630+563=6193

*square 40 to 50...( take 15 as common factor )

E.g1)if 42 square =

step 1) 10-2=8

step 2) 8 square=64,

step 3) 15(constant)+2(2digits)=17

step 4) step3 and step 2 together= 1764

E.g2) if 48 square=

step 1) 10-8=2

step 2)  2 square= 04

step 3) 15(constant)+8(2digits) =23

step 4) step3 and step 2 together=2304

*square 50 to 60... ( take 25 as common factor )

E.g 1) if 52 square=

step 1) 2nd digits (2) square= 04

step 2) 25( constant)+2(2nd digit)=27

step 3)step 2 and step 1 together = 2704

E.g 2) if 58 square=

step 1) 2nd digits(8) square= 64

step 2) 25 (constant)+8(2nd digit)=33

step 3) step 2 and step 1 together= 3364

*square 90 to 99... (take 80 as common factor)

E.g 1) if 92 square=

step 1) 10-2=8

step 2)  8 square= 64

step 3) 80(common no)+(2*2)=84

step 4 ) step3 and step 2 together=8464

 E.g 2) if 98 square=

step 1) 10-8=2

step 2)  2 square= 04

step 3) 80(common no)+(8*2)=96

step 4 ) step3 and step 2 together=9604

* multiplication- series of 100

E.g)  102*103=10506

tricks:

a) take 100 as common factor

b) add 2+3 in 100=105

c)2*3=06

b and c =10506 do other ...

*EVERY 9 square ...

E.g)if 99 square 

step 1)99-1=98

step 2) 99 is two digit no so we have to take two digit no 1 is common 0 is add extra =01   

step 3) step 1 and 2 together=9801

E .g) if 999 square

step 1) 999-1=998

step 2) 999 is three digit no so we have to take three digit no 1 is common 0 is add extra =001

step 3) step 1 and 2 together =998001

*To multiply any no by 5,

E.g 1)

126*5=630

step 1) 126/2=63

step 2) 63*10=630

E.g 2)

 432*5=2160

step 1) 432/2=216

step 2) 216*10=2160

* square of 94=8836

94 is 6 less than 100 so subtract 6 from 94

Multiplication of two numbers that differ by 6 (This trick only works if you have memorized or can quickly calculate the squares of numbers.

If the two numbers differ by 6 then their product is the square of their average minus 9.
Let me explain this rule by taking examples
10*16 = 13^2 - 9 = 160
22*28 = 25^2 - 9 = 616

Example.
Understand the rule by 1 more example
997*1003 = 1000^2 - 9 = 999991

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Multiplication of 2 two-digit numbers where the first digit of both the numbers are same and the last digit of the two numbers sum to 10 (You can’t use this rule for other numbers)

Let me explain this rule by taking examples To calculate 56×54: Multiply 5 by 5+1. So, 5×6 = 30. Write down 30. Multiply together the last digits: 6×4 = 24. Write down 24. The product of 56 and 54 is thus 3024.

Example.
Understand the rule by 1 more example
78*72 = [7*(7+1)][8*2] = 5616