The formula to be used is
[tex]\begin{gathered} d=rt \\ \Rightarrow(\frac{1}{r})d=(\frac{1}{r})rt \\ \Rightarrow\frac{d}{r}=t \end{gathered}[/tex]Therefore,
[tex]t=\frac{10.2}{0.5}=20.4[/tex]Thus, the answer is t=20.4hr
Suggested method.
[tex]\begin{gathered} d=10.2,r=0.5 \\ \text{and} \\ d=rt \\ \Rightarrow10.2=0.5t \\ \Rightarrow\frac{10.2}{0.5}=\frac{0.5t}{0.5} \\ \Rightarrow\frac{10.2}{0.5}=t \\ \Rightarrow t=20.4 \end{gathered}[/tex]The answer is t=20.4 hours
