Cassius drives his boat upstream for 45 minutes. It takes him 30 minutes to return downstream. His speed going upstream is 3 miles per hour slower than his speed going downstream. Find his upstream and downstream speed

Upstream speed = 45 miles per hour, downstream speed = 60 miles per hour

Let his speed downstream =S His speed upstream =S - 3 [S - 3] * 0.75 =S * 0.5, solve for S 0.75S - 2.25 =0.5S - 2.25 =0.5S - 0.75S - 2.25 = - 0.25S S = - 2.25 / - 0.25 S = 9 mph - his speed downstream 9 - 3 = 6 mph - his speed upstream.