How we worked it out
Updated as you change the numbers.
- Divide by the rounding step, round to a whole number by the chosen rule, then multiply back.
Method and assumptions
Half up rounds 2.5 to 3; half to even rounds 2.5 to 2 and 3.5 to 4, so halves balance out over many numbers. Always up and always down are the ceiling and floor at the chosen step. Significant figures count from the first non-zero digit.
Questions
What is 1,234.5678 to 3 significant figures?
1,230.
Sources
Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.