So,
Before I do anything, I would like to ask the question that should subconsciously and instantaneously pop into everyone's heads: Why is Violet calculating mills? Where does she live? Either it is a place where the value of money is very high, or Violet is very poor, so mills factor into prices.
To round $129.207 to the nearest cent (penny), find the mill's place, which is the 7.
Since 7 is greater than or equal to 5, round up.
$129.207 --> $129.21
Violet's dress will cost $129.21 rounded to the nearest cent.
