First, you can know how many minutes are 8 hours using the rule of three like this
[tex]\begin{gathered} 1\text{ hour}\rightarrow60\text{ minutes} \\ 8\text{ hours }\rightarrow\text{ x minutes} \end{gathered}[/tex][tex]\begin{gathered} x=\frac{8\text{ hours }\ast\text{ 60 minutes}}{1\text{ hour}} \\ x=480\text{ minutes} \end{gathered}[/tex]Now, using the rule of three again, you can find out how many gifts Dracula would wrap in 8 hours if she wrapped 3 gifts every 20 minutes
[tex]\begin{gathered} 20\text{ minutes}\rightarrow3\text{ presents} \\ 480\text{ minutes}\rightarrow x\text{presents} \end{gathered}[/tex][tex]\begin{gathered} x=\frac{480\text{ minutes}\ast3\text{ presents}}{20\text{ minutes}} \\ x=\frac{1440}{20}\text{ presents} \\ x=72\text{ presents} \end{gathered}[/tex]Therefore, Dracula would wrap 72 gifts in 8 hours if he wrapped 3 gifts in 20 minutes
