Question 450441
A rowing team practices rowing 2 miles upstream and 2 miles downstream.
 The team can row downstream 25% faster than they can row upstream.
 Let r represent their rate upstream.
 Write and simplify an expression for the amount of time they spend rowing. 
:
Let r = rowing speed upstream
then
1.25r = rowing speed downstream
:
Write a time equation; time = dist/speed
rowing time = {{{2/r}}} + {{{2/(1.25r)}}}
simplify
r.t = {{{(2(1.25r)+2r)/(r*1.25r)}}} = {{{(2.5r+2r)/(1.25r^2)}}} = {{{(4.5r)/(1.25r^2)}}}
cancel r
r.t. = {{{4.5/(1.25r)}}}, simplified expression for time spent rowing