Question 402008
Shannon's rate = r + 30
Chris's rate = r
==> {{{75/r = 120/(r+30)}}}
==> 75(r+30) = 120r
==> 75r + 2250 = 120r
==> 2250 = 45r
==> r = 50 mph, the rate of Chris, and
r + 30 = 80 mph, the rate of Shannon.