I created this chart to help my students find the least common denominator when we started working on adding and subtracting fractions. They fill it out on their own so it's also good practice for working on multiplication facts. It goes up to 10 x 20. When it's filled out, students can look at the denominators of the fractions, find those numbers on the right of the chart, then move slowly from left to right across the chart till they find the smallest number they both divide into. It was a lot of help!