The rules for rounding numbers vary from country to country. The following are some of the methods for rounding numbers:

  • Round numbers up or down using 0.5 as the determining value. For example, round numbers in the range 2.1-2.4 down to 2.0, and numbers in the range 2.5-2.9 up to 3.0.
  • Round numbers up or down using 0.25 as the determining value. For example, round numbers in the range 2.0-2.25 down to 2.0, and numbers in the range 2.26-3.0 up to 3.0.