Journal for Research in Mathematics Education, Vol. 19, No. 2 (Mar., 1988), pp. 157-168 (12 pages) Twenty secondary mathematics teachers described their thinking as they solved four proportion ...

Proportion also describes how the sizes of different parts of a piece of art or design relate to each other. The proportions of a composition will affect how pleasing it looks and can be used to ...

Margaret Rathouz, Nesrin Cengiz, Angela Krebs, Rheta N. Rubenstein, Tasks to Develop Language for Ratio Relationships, Mathematics Teaching in the Middle School, Vol. 20, No. 1 (August 2014), pp.