When rounding, you only look at the decimal right behind the one you'll be rounding to.
If this is 5 or more, you round up , otherwise you just cut off (or round down, which is the same).
Common mistake: Rounding in steps.
Task : Round
3rd decimal is 9 so the 8 before is is rounded up to 9
2th decimal is now 9, so 3th decimal is rounded up to 5
1st decimal is now 5, the answer is
If you want a whole number, as in this case, you only look at the first decimal, which is 4, so the right answer is
(Even 5.4999999 would be rounded to 5)