Janice is making geometric cutouts for the math exhibition at her school. Help her identify the shapes with right angles.
Janice and Jasmine were each given a piece of ribbon of equal length. Janice cuts her ribbons into equal lenghts of 20 m, while Jasmine cuts her ribbons into equal lengths of 15 m. If there was no remainder in both cases, find the shortest possible lenghth of ribbon given to them.