What concept refers to numbers that are easy to work with on a number line?

The concept that refers to numbers that are easy to work with on a number line is landmark numbers. Landmark numbers serve as reference points that help individuals understand the position and relationship of other numbers in relation to them. For instance, on a number line, whole numbers such as 0, 5, 10, and 100 are considered landmark numbers because they are often used as benchmarks for estimation and comparison. They help in visualizing intervals and operations, making calculations and comparisons more intuitive.

Landmark numbers are particularly useful in teaching and learning because they help students grasp more complex mathematical concepts by establishing a clear visual reference. By anchoring calculations to these familiar points on the number line, learners can more easily navigate operations and understand numerical relationships.