Vedic mathematics is a system of mathematics consisting of a list of 16 basic sūtras, or aphorisms. They were presented by a Hindu scholar and mathematician, Bharati Krishna Tirthaji Maharaja, (He was also the Shankaracharya of Govardhan Math, Puri, from 1925 until he passed away in 1960.)


Tirthaji claimed that he found the sutras after years of studying the Vedas. 

[source: wikipedia]

In the first lesson of Vedic Maths, let's understand: 

Multiplication by 5
Instead of multiplying a number by 5, it's better to multiply it by 10 first, and then divide the result by 2. For example, 235x5=2350/2=1175
Same way,  you can, multiply by 50 also. 

Multiplication by 4
The method says, replace it with a repeated operation by 2 eg. 124x4=248x2=4

Multiplication by 25
Multiply first by 100 and then you can divide by 4. eg. 37x25=3700/4=1850/2=925.

Multiplication by 8
You can replace  with a repeated operation by 2. For example 124x8=248x4=496x2=992.

Multiplication by 45
Multiply first by 90 and then divide the result by 2. For example 37x45=37x90/2=3330/2=1665
Or put into use , this method  37 x45 = 37 (100/2  -10/2)= 3700/2-370/2=1850-185=1665

Multiplication by 55
Multiply first by 110and then divide by 2. For example37x55=37x110/2=4070/2=2035

Multiplication by 75
Multiply first by 300 and then divide by 4 .For example37x75=37x300/4=11100/4=2775

Multiplication by 125
Multiply first by 500 and then divide by 4 For example37x125=37x500/4=18500/4=4625

Multiplication by 150
Multiply first by 300 and then divide by 2 For example37x150=37x300/4=11100/2=5550

Multiplication by 175
Multiply first by 700 and then divide by 4 For example37x175=37x700/4=25900/4=6475

Multiplication by 225
Multiply first by 900 and then divide by 4 For example37x225=37x900/4=33300/4=8325

Multiplication by 275
Multiply first by 1100 and then divide by 4 
For example37x275=37x1100/4=40700/4=10175