Answer:
[tex]\frac{1}{4}[/tex]
Step-by-step explanation:
[tex]\frac{72}{80} = \frac{18}{20}[/tex]
so, [tex]\frac{18}{20} - \frac{13}{20} = \frac{18-13}{20} = \frac{5}{20}[/tex]
[tex]\frac{5}{20} = \frac{1}{4}[/tex]
