# Math Help - find the common denominator

1. ## find the common denominator

b c d
__ x __ x ___
2 2 2
cd bd bc

I seriously do not understand fractions !
When I view this is looks wieird, it is b over cd squared times c over bd squared times d over bc squared. How do I find a common denominator with variables?

2. ## Re: find the common denominator

The LCD will be (bcd)^2.
For each factor in the denominators, you'll have a corresponding factor in the LCD.

Edit... Apparently, we aren't adding fractions...

3. ## Re: find the common denominator

Originally Posted by rikkiann
b c d
__ x __ x ___
2 2 2
cd bd bc

I seriously do not understand fractions !
When I view this is looks wieird, it is b over cd squared times c over bd squared times d over bc squared. How do I find a common denominator with variables?
Hang on, is it $\displaystyle \frac{b}{cd^2} \times \frac{c}{bd^2} \times \frac{d}{bc^2}$ or is it $\displaystyle \frac{b}{(cd)^2} \times \frac{c}{(bd)^2} \times \frac{d}{(bc)^2}$?

Either way, you don't need a common denominator when multiplying fractions, you just need to times tops and times bottoms, then cancel any common factors.