Adding Fractions (Vedic Maths style)

Vedic Maths originated from India and are based on 16 principles or 'sutras' . The section below is extracted from http://www.vedicmaths.org/Introduction/Tutorial/Tutorial.asp

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The easy way to add and subtract fractions.

Use VERTICALLY AND CROSSWISE to write the answer straight down!

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Multiply crosswise and add to get the top of the answer:
2 x 5 = 10 and 1 x 3 = 3. Then 10 + 3 = 13.
The bottom of the fraction is just 3 x 5 = 15.
You multiply the bottom number together.

So:

• Subtracting is just as easy: multiply crosswise as before, but the subtract:
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Understanding it is not so difficult. It's simply the short cut of equivalent fractions or the LCM method that we use (just that sometimes it is not the LCM but rather CM that is being used).

E.g. The second example.

6/7 = 18/21

2/3 = 14/21

so 6/7 - 2/3 = 4/21