Arithmetic & Basics
Basic

Rounding Rule

Round up if the next digit is 5+, otherwise round down.

Formula

5 or more↑, 4 or less↓5\text{ or more} \uparrow, \ 4\text{ or less} \downarrow

Variables

Example

4.7 → 5, 4.3 → 4

Did You Know?

Banks often use "round half to even" (banker's rounding) to avoid a systematic upward bias when rounding millions of transactions.

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