Common Denominator

Fractions have the same number at the bottom

5/  3/   4/6

These all have the same common denominator

http://www.mathsisfun.com/numbers/common-denominator.html



Least Common Denominator
http://www.mathsisfun.com/least-common-denominator.html


http://www.youtube.com/watch?v=KPZnoF0V9ZI