Question

how do i find a LCD

Answer 1

The LCD is the smallest whole number that will divide into each denominator.

Read this information at this web site

http://www.helpwithfractions.com/least-common-denominator.html

and then try watching a video at khan academy on LCM.

http://www.khanacademy.org/math/arithmetic/factors-multiples/v/least-common-multiple--lcm

You can watch video as much as you like. Then come back with a particular problem you would like worked out.