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Add Fractions Fast

Add Fractions Fast

The hardest thing about fractions is adding them. Multiplication is easy, but addition is usually taught as a complex multi-step process. It's a real pain.

But it doesn't have to be that way. Here's a trick that lets you take two fractions, add them in your head, and shout out the result. You'll look like a math wizard!

Here it is..

Take the two fractions to be added..

a c
b d

Take the diagonal numbers (top left and bottom right) and multiply them, a*d

Do the other diagonal, c*b

Add the two results (a*d)+(c*b)

That's the "top" (numerator) of the answer.

The "bottom" (denominator) of the answer is much easier, it's just b*d

You're done!

Did you notice the pattern? It's two diagonals and a base, like this..


A lot of mathematics involves patterns.

Content written and posted by Ken Abbott