**Banking,T.E.T(Teaching Eligibility Test,I.A.S**etc. all needs speed in computing for selecting in exam.So a person should have some mathematical tricks for faster computing.Here I am try to give to all of you some tricks Which can help you for a good future.

**Multiplying with 5**- Any 2 digit number multiply by 99
- Multiplying any number by 11
- The square of any number having last digit 5

Let us take a number 5887.We have to multiply it with 5

Eg. 5887*5=Just divide it to by 2.After divide we get a number=2943,last may add 0

which give 2943.5,ignore remainder the

**Ans is=29435**

Eg.let a 2 digit number is 44.We have to multiply it with 99

**44*99=(44-1)(100-44)=4356**

Let us take a number 42.We have to multiply it by 11

**42*11=(4+2)=6**

now add into 42

**The answer is=4**

__6__2

Let us take a number 85.We have compute its square

85*85= Firstly compute square of last digit which always 25

then multiply all digit remains with its successor.

**85*85=8*(8+1)25=7225**

add some more example. easy to understand..

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