Question

One third as a decimal

Answer 1

.333333333 ect. so the three is a repeating decimal. hope this helps. :))

Answer 2

One third is one of those rational numbers that can never be
exactly written as a decimal.  To change a fraction into its
decimal, you divide the top number by the bottom number,
and the quotient is the decimal form of the fraction. 
When you divide  1  by  3 , you get  .333... and the 3s never
stop.  They just keep going on forever. 
That's called a "repeating" decimal.