$V \propto l$

$\mathrm{V}=\mathrm{k} l$

Now, it is given $\mathrm{E}=1.1$ $volt$ for $l_{1}=440\, \mathrm{cm}$ and $V=0.5$ $volt$ for $l_{2}=220\, \mathrm{cm}$

Let the error in reading of voltmeter be $\Delta \mathrm{V}$ then, $1.1=400\, \mathrm{K}$ and $(0.5-\Delta \mathrm{V})=220\, \mathrm{K}$

$\Rightarrow \frac{1.1}{440}=\frac{0.5-\Delta V}{220}$

$\therefore $ $\Delta V=-0.05 \text { volt }$