Both terminating and repeating decimals have a geratrix fraction. Irrational decimals (e.g., (0.1010010001\ldots)) do not. Case 1: Terminating Decimal Write the decimal as a fraction with a power of 10 in the denominator, then simplify.
(0.\overline72) (x = 0.727272\ldots) (100x = 72.727272\ldots) Subtract: (100x - x = 72 \Rightarrow 99x = 72 \Rightarrow x = \frac7299 = \frac811) Case 3: Mixed Repeating Decimal Let (x) be the decimal. Multiply by a power of 10 to move the decimal point to just before the repeating block, and by another power to include the whole repeating part. Subtract. exercicios sobre fração geratriz
(0.\overlineabc\ldots = \frac\textrepeating block10^n - 1) where (n) = number of digits in the block. Both terminating and repeating decimals have a geratrix