Ratios & rates

A ratio is a comparison of two numbers (or quantities) using division. For example, if I have 4 hearts and 3 stars, then the ratio of hearts to stars is 4:3 (four to three). We can often "translate" between ratio language and fraction language. Lastly I work several word problems that involve ratios and fractions, using a bar (or block) model, a powerful visual aid that helps students from grade 4 onward solve problems that would otherwise require algebra.