Unit Fractions: Terminating, Repeating or Never-Ending?
Consider the unit fraction 1/n, for 
. What patterns do you notice in the decimal form of these unit fractions? What do you notice about the terminating decimals? The repeating decimals? The decimals that repeat after a delay? Using a spreadsheet may help in your investigations.
Extensions:
Which unit fraction () has the decimal expansion of longest period?