Reply To: Lesson 8-2: Ratio and Rate Reasoning – Discussion

[Diane Hamilton]

Wow, this module gave me lots to think about! I remember learning to cross-multiply in high school and never really understanding how a fraction could also be a ratio. And I never understood why we were making graphs of algebraic equations! I’ve only recently understood that the line on a graph is depicting the relationship between x and y, ad infinitum. Seeing all the relationships laid out in this module was really helpful, both up and down the ratio table as well as across. I teach grades 3-6 math, so some of this material is where my students are heading, not what I will be teaching them. But is it ever helpful to better understand how patterning and ratio tables are leading to the constant of proportionality and functional reasoning.

I think that when a rate is not going to be expressed in whole numbers, a ratio might be a better way to go. With the rice example a rate of 2 water per 1 rice is easy to understand, but if the ratio were 3:2, giving a rate of 1.5 per 1, in some contexts that might not make sense (people with brown eyes:people with blue eyes for example).