Cell Value Differs From Real Cell Value

I have 1 column that contains numbers, for example:

0.50
0.655
0.7898

But in the formula bar, for the first row (0.50), I get 0.499999999999. Why does the cell value differs from the value in the formula bar?

I need to format that column, so that every value contains 9 characters and is rounded. For example, 0.50 needs to become 000000.50

I already have:

Dim rCell As Range
Dim rRng As Range
Set rRng = ws.Range("G2:G999")
For Each rCell In rRng.Cells
If rCell = "" Then Exit For
rCell.NumberFormat = "0000000.00"
rCell.Value = WorksheetFunction.Round(rCell.Value, 2)
Next rCell

And it works! The value in the cell is 000000.50! But when you click that cell, the value in the formula bar is 0.5, so when I export to .txt file, I get 0.5 instead of the 000000.50 that the cell is showing?