Answer :
[tex]\frac{13}{5a^{2}} = \frac{blank}{10a^{2}b^{3}}[/tex]
[tex]\frac{13}{5a^{2}} = \frac{blank}{5a^{2}(2b^{3})}[/tex]
[tex]\frac{13}{1} = \frac{blank}{2b^{3}}[/tex]
[tex]blank = 13(2b^{3})[/tex]
[tex]blank = 26b^{3}[/tex]
[tex]\frac{13}{5a^{2}} = \frac{blank}{5a^{2}(2b^{3})}[/tex]
[tex]\frac{13}{1} = \frac{blank}{2b^{3}}[/tex]
[tex]blank = 13(2b^{3})[/tex]
[tex]blank = 26b^{3}[/tex]