This module gives support for rational numberarithmetic.
此模块提供对有理数算法的支持。
2
A regular system (of number-words) also makes arithmetic clearer to understand.
数字的规律系统也让算术更加清晰易懂。
3
Arithmetic progression: a number of its change in the process, after each change in the amount of change several times before, that is the product of the relationship.