Question 1065217
RT=D, constant travel rate rule for rate R, time T, distance D.

<pre>
r, speed in absence of wind
w, speed of wind


              SPEED     TIME     DISTANCE

WITHWIND      r+w       9        11790

AGAINST       r-w       7         5670
</pre>

{{{system((r+w)(9)=11790,(r-w)(7)=5670)}}}