By what rational number should

Let the number be $\mathrm{x}$.

Now,

$\mathrm{x} \times \frac{-8}{39}=\frac{1}{26}$

$\Rightarrow \mathrm{x}=\frac{1}{26} \div \frac{-8}{39}$

$\Rightarrow \mathrm{x}=\frac{1}{26} \times \frac{39}{-8}$

$\Rightarrow \mathrm{x}=\frac{39}{-208}$

$\Rightarrow \mathrm{x}=\frac{39 \times-1}{-208 \times-1}$

$\Rightarrow \mathrm{x}=\frac{-39}{208}$

$\Rightarrow \mathrm{x}=\frac{-39 \div 13}{208 \div 13}$

$\Rightarrow \mathrm{x}=\frac{-3}{16}$