Question

How can the bar symbol be used to show the quotient of 10 divided by 12 if the division is carried on forever

Answer 1

Since, in its decimal expansion, you'd have

$\dfrac{10}{12}=\dfrac{5}{6}=0.833333\ldots$

We use the bar symbol over the digits that repeat indefinitely, so, in this case, we'll write a single "3" with an overbar:

$\dfrac{10}{12}=0.8\overline{3}$