In order to go to college, hank goes from working full-time making $28,000 per year to working part-time at half the salary for two years. the cost of his education will be $5,000. if hank makes $33,000 per year after getting his degree, approximately how many years will it take him to recover his investment?

I assume that he will spend 4 years in college and that the cost is per year: so the total cost of the education is :

(28 000/2)*4+5000*4=56000+10 000=66000 so his total cost of attending the college is 66 000 dollars

Every year he will make 33000-28000=5000. So every year he will make 5 000 dollars more.
which means that he needs 66000/5000=13.2 years to recover from his investment!