How do you show the group of digits that repeat in a repeating decimal?

Question

by printing them in italics

by putting a bar over them

I put them in parentheses

Answer 1

To indicate the group of digits that repeat in a repeating decimal, the most common method is to put a bar (also called a vinculum) over the repeating part. For example, the decimal representation \( 0.\overline{3} \) represents the repeating decimal \( 0.3333\ldots \).

Putting the repeating digits in parentheses is also a method sometimes used, but the standard notation is to use the bar. Printing the digits in italics is not a conventional way to represent repeating decimals.

So, the correct answer is: by putting a bar over them.