So how does the 12's shortcut work?
Let's take a look.

12 X 7

The first thing is to always multiply the 1 of the twelve by the
number we are multiplying by, in this case 7. So 1 X 7 = 7.

Multiply this 7 by 10 giving 70. (Why? We are working with BASES here.
Bases are the fundamentals to easy calculations for all multiplication tables.
To find out more check out our Vedic Maths ebook at www.vedic-maths-ebook.com

Now multiply the 7 by the 2 of twelve giving 14. Add this to 70 giving 84.

Therefore 7 X 12 = 84

Let's try another:

17 X 12

Remember, multiply the 17 by the 1 in 12 and multiply by 10
(Just add a zero to the end)

1 X 17 = 17, multiplied by 10 giving 170.

Multiply 17 by 2 giving 34.

Add 34 to 170 giving 204.

So 17 X 12 = 204

lets go one more

24 X 12

Multiply 24 X 1 = 24. Multiply by 10 giving 240.
Multiply 24 by 2 = 48. Add to 240 giving us 288

24 X 12 = 288 (these are Seriously Simple Sums to do aren’t they?!)