Rounding decimals is very similar to rounding other numbers. If the hundredths and
thousandths places of a decimal is forty-nine or less, they are dropped and the
tenths place does not change.

For example, rounding 0.843 to the nearest tenth would give 0.8.

If the hundredths and thousandths places are fifty or more, the tenths place
is increased by one. The decimal 0.866 rounded to the nearest tenth is 0.9