Question 21644
Time up + time down = 120 sec -12 sec = 108 sec
Up data: distance = 240 m; rate= x; time= 240/x
Down data: dist = 240 m; rate = x+1; time = 240/(x+1)
EQUATION:
  Time up + Time down = 108 sec
   240/x + 240/(x+1) = 108
   1/x + 1/(x+1) = .45
     2x +1= .45(x^2+x)
  9x^2-31x - 20 =0
*[invoke quadratic "x",9,31,-20]
Looks like rate up is 0.55... meters/sec
Cheers,
Stan H.