In given diagram ideal voltmeter $V$ reads $1.45\,V$ then relation between $r_1$ and $r_2$ is
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By parallel combination

$I=\frac{1.5-1.3}{r_{1}+r_{2}}=\frac{0.2}{r_{1}+r_{2}}$

$\mathrm{V}=1.3+\mathrm{Ir}_{1}$

$1.45=1.3+\frac{0.2 \mathrm{r}_{1}}{\mathrm{r}_{1}+\mathrm{r}_{2}}$

$\Rightarrow 0.15=\frac{0.2 \mathrm{r}_{1}}{\mathrm{r}_{1}+\mathrm{r}_{2}}$

$\Rightarrow 3\left(\mathrm{r}_{1}+\mathrm{r}_{2}\right)=4 \mathrm{r}_{1}$

$\Rightarrow 3 r_{2}=r_{1}$

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