Quite simple, actually...
So,
Brooke makes $28,150 per year...so..to find 5 years...take..
28,150*5=140,750, after 5 years, Brooke makes this much.
Also, for, Jake..take..
31,380*5=156,900
after 5 years, Jake makes this much.
To see how much Jake earns more than Brooke..take.
156,900-140,750=16,150
Jake earns $16,150 more than Brooke.