Question

What number does 584 round to? 580 or 585?

Answer 1

Rounding to the nearest 5, it rounds to 585. This is because it is closer to 585 than 580. However, rounding to the nearest 10, it rounds to 580.

Answer 2

580
You can remember this by saying
5 or more let it soar
4 or less let it rest
Which means if there's 5 or more round up but if it's 4 or less round it down