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Here's an example that might help:
If x=0.1\dot{6}, then 10x=1.\dot{6}
1.\dot{6} is also x+1.5
So \eqalign{10x&=x+1.5 \cr \Rightarrow 9x&=1.5 \cr \Rightarrow 18x&=3 \cr \Rightarrow x&=\frac3{18} = \frac16}
What do you notice about these families of recurring decimals?