It's complicated. Caterham actually received more prize money than Marussia last year. http://bleacherrepor...-and-per-season
Assuming a similar prize fund:
If Marussia come 10th and Caterham 11th then Marussia will get about $35 million and Caterham nothing (because Caterham wouldn't qualify for column 2 payments).
If Caterham and Sauber both beat Marussia then Marussia will get about $14 million (because they came 10th last year would still be eligible for column 2)
If Marussia manage to hold on to 9th then it could potentially be worth about $52.5 million
Pocket change for the guys at the front, but huge for a small team which can only afford £2000 in upgrades for one race.
If I understand it correctly, if Marussia finish 9th this year, they will get $52.5 million, but that still would be $49 million in case of finishing 10th, and 0 in case of finishing 11th.
So it really shows the game for them is about being inside top10 rather than beating Sauber. When it comes to the prize money, because beating team like Sauber could be a boost for their confidence, prestige, sponsorship interest etc.
But the best situation for F1 could be, if Caterham also beat Sauber this year. Then all 11 teams would qualify to column 1 payment and there wouldn't be one team clearly hampered much than others.