Question 837104
r = rate going down the hill


______________speed___________time______________distance
UPHILL________r-1.5___________4________________{{{(r-1.5)*4}}}
DOWNHILL_______r_____________168/60=2.8_________{{{r*(2.8)}}}


The division by 60 for downhill is because 60 minutes make 1 hour.
Both directions are the same distance quantity.
{{{highlight_green((r-1.5)*4=r(2.8))}}}


{{{4r-6=2.8r}}}
{{{4r-2.8r=6}}}
{{{1.2r=6}}}
{{{r=6/1.2}}}
{{{highlight(r=5)}}}