Question 805593
r*t=d
(490-c)*t=1600
490*t-c*t=1600

(490+c)*t=2400
490*t+c*t=1600
490*t-c*t=2400
add
980t=4000
t=4000/980
t=4.08163265 hr
490*4.08163265+c*4.08163265=2400
2000.0+c*4.08163265=2400
c*4.08163265=400.0
c=400.0/4.08163265
c=98.0 mph wind
check
(490+c)*t=2400
(490+98)*4.08163265=2400
(588)*4.08163265=2400
2400.0=2400

(490-c)*t=1600
(490-98)*4.08163265=1600
(392)*4.08163265=1600
1600.0=1600
ok