Let r = rate of the slower group and r + (1/2) is the rate of the faster group.
Each group walks 200 hours and the total distance traveled is 1050 miles.
One group travels 200r and the other group travels 200(r+.5)
200r + 200r + 100 = 1050
400r=950
You can do the necessary arithmetic.
Paul M.
03/25/19
Elio A.
Thank you so much!03/25/19