Students identify, extend, and compare numerical and arithmetic patterns in lists and tables, including whole-number patterns and familiar decimal sequences generated by repeated addition, subtraction, multiplication, or division, and represent corresponding pairs on coordinate grids to predict missing or later values and explain term-to-term or input-based rules. Students generate and complete input-output tables, distinguish inputs from outputs, and infer or apply numerical rules involving a fixed operation or two straightforward operations. Students evaluate grouped numerical expressions with parentheses using whole-number addition, subtraction, multiplication, and division, applying grouping and multiplication or division before addition or subtraction, and use variables to represent unknowns in solving and checking one-step equations and contextual problems with appropriate units.