Curated OER
Closure Property
In this closure property activity, students solve 10 different problems using the closure property. First, they determine whether the numbers and the answer are real numbers. Then, students determine if the given sets are either closed...
Cuemath
Cuemath: Real Numbers
A comprehensive guide for learning all about real numbers and their important properties with solved examples and practice questions.
Oswego City School District
Regents Exam Prep Center: Closure Property
This site gives a very clear discussion on the topic of closure of sets over an operation with many examples.
Cuemath
Cuemath: Natural Numbers
We see numbers everywhere around us - measuring the temperature, counting money, telling the time, etc. The numbers that are used for counting objects are called "natural numbers". This article explains the properties of natural numbers...