Data:
d = 336 mi (total distance)
v1 = 60 m/h (speed 1)
v2 = 48 m/h (speed 2)
In order to compute the time in hours, we can divide the distance by each speed.
[tex]\begin{gathered} t_1=\frac{d}{v_1}=\frac{336mi}{60\frac{mi}{h}}=5.6h \\ t_2=\frac{d}{v_2}=\frac{336mi}{48\frac{mi}{h}}=7h \end{gathered}[/tex]Therefore, driving at 60mph Darius will spend 5.6 hours and driving at 48 mph he will spend 7 hours.