[tex]S_{1} =168 \ mil \\ t_{1} =3,5\ h \\ S_{1} =v_{1} *t_{1} /:t _{1} \\ \frac{S_{1} }{t_{1} } =v_{1} \\ \frac{168}{3,5} =48=v_{1} \\ v_{2} =v_{1} +5=48+5=53 \ mil \ per \ hour \\ t_{2} =2,25 hour \\ S_{2} =v_{2} *t_{2} =53*2,25=119,25 \\ S_{1} +S_{2} =168+119,25=287,25 \ mil[/tex]