If the decimal is 5 or greater you round up, 4 or less round down.
Examples:
4.5 - round up to 5.
6.3 - round down to 6.
If the number has decimals in the hundredths place first round the last number up then the first.
Example:
2.46 - round to 2.5 then round to 3.
I hope this helps! If you have any questions pls reply and I will try to get back as soon as possible.
