Question 1126957
w, speed of wind

Assuming same amount of time against the wind


{{{d=4(45+w)}}}
-
{{{(45-w)*4=0.6*4(45+w)}}}
{{{45-w=(3/5)(45+w)}}}
{{{225-5w=3(45+w)}}}
{{{8w=225-135}}}
{{{8w=90}}}
{{{highlight(w=11&1/4)}}}