Question 983744
Need 10000 feet;
Already done 550 feet;
Still need to finish 10000-550=9450 feet.


{{{9450*feet*(1/210)(minutes/feet)}}}


{{{9450/210=945/21=5*189/21=5*7*27/21=5*7*3*3*3/(3*7)}}}


{{{highlight(45*minutes)}}}