First of all, as a football fan, 50 passing yards crossing out a sack doesn't make sense.
Formatting this a bit better, we have:
Passing Yards
Dak: 256 Colt: 315 (+300 bonus)
Rushing Yards
Dak: 31 Colt: 16
INTs
Dak: 1 Colt: 2
Sacks
Dak: 2 Colt: 1
Passing TDs (0-40 yards)
Dak: 1 Colt: 2 (you only listed 3 yardages for Colt's touchdowns, yet said he had 4, so you'll need to edit the final answer. In addition, I don't know if passing TDs from 50+ yards are counted as a passing TD from 40+ yards, 50+ yards as well, so I'll assume that it doesn't)
Passing TDs (40-50 yards)
Dak: 1 Colt: 0
Passing TDs (50+ yards)
Dak:0 Colt: 1
To figure this out, instead of going and calculating both scores separately, what I will do is subtract Dak's count from Colt's count for each stat, and that difference will therefore be how much the brothers won from that stat. If it's negative, the brothers lose that much money, and I'll add the numbers at the end. Note that the 300 yard bonus is not counted in this, so I'll add 5 to Colt's number at the end. To figure out the rushing/passing yards, we can simply divide the numbers by 25/10 because it's for every amount of yardage, you get a point. For all others, we simply multiply the amount by the amount per sack, INT, rushing touchdown, etc.. Without further ado, here's our end number equation:
5+(315-256)/25+(16-31)/10+(2-1)*(-3)+(1-2)*(-2)+4*(4-2)+2*(0-1)+3*(1-0)=13.86
Feel free to ask further questions, and Happy Thanksgiving!