Simplify the following text for a Grade 9 native English-speaking person.
Original: The magnitude of a mathematical object is its size : a property by which it can be compared as larger or smaller than other objects of the same kind ; in technical terms , an ordering ( or ranking ) of the class of objects to which it belongs .
Simplified: The magnitude of a mathematical object is its size : a property by which it can be larger or smaller than other objects of the same kind .