7 Pipes, Tubes, and Beakers: New Approaches to Teaching the Rational-Number System | How Students Learn: History, Mathematics, and Science in the Classroom | The National Academies Press
![Prove or disprove that if r is rational and s is rational, then r + s must be rational - GeeksforGeeks Prove or disprove that if r is rational and s is rational, then r + s must be rational - GeeksforGeeks](https://media.geeksforgeeks.org/wp-content/uploads/20220818113608/RealNumber.jpg)
Prove or disprove that if r is rational and s is rational, then r + s must be rational - GeeksforGeeks
![An example of how the development of rational and irrational numbers... | Download Scientific Diagram An example of how the development of rational and irrational numbers... | Download Scientific Diagram](https://www.researchgate.net/publication/345368475/figure/fig1/AS:954832294797314@1604661167859/An-example-of-how-the-development-of-rational-and-irrational-numbers-was-introduced-in.jpg)