Subtraction In Bars

Let $x=4.\overline{86} \ ...(1)$ .

Multiplying by $100$ .

$\Rightarrow 100x=486.\overline{86} \ ...(2)$

Subtracting $(1)$ from $(2)$ .

$\Rightarrow 99x=482$

$\Rightarrow x=\color{#3D99F6}{\dfrac{482}{99}}$

And $y=3.\overline{95} \ ...(3)$ .

Multiplying by $100$ .

$\Rightarrow 100y=395.\overline{95} \ ...(4)$

Subtracting $(3)$ from $(4)$ .

$\Rightarrow 99y=392$

$\Rightarrow y=\color{#20A900}{\dfrac{392}{99}}$ .

$\therefore x-y=\color{#3D99F6}{\dfrac{482}{99}}-\color{#20A900}{\dfrac{392}{99}}=\dfrac{90}{99}=\boxed{0.\overline{90}}$