How to classify each number as natural, whole, integer, irrational, or real: [math]\frac {12}{3}[/math], [math]15[/math], [math]\frac {π}{2}[/math], [math]-891[/math], [math]3.3[/math] - Quora
What is the difference between integers, whole numbers, real numbers, rational and irrational numbers? - Quora
![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)