Why do we round up 0.5000 to 1 instead of rounding down to 0?

Question

Why do we round up 0.5000 to 1 instead of rounding down to 0?

In: 12

Answer 1

Because no matter how many decimal places you use, it gives an exactly equal number rounding up as rounding down.

1 decimal place: .0 through .4 round down, .5 through .9 round up. Five each way.

2 decimal places: .00 through .49 round down, .50 through .99 round up. 50 each way.