First, calculate the total cost of attending college.
Tuition: $10,000 * 4 = $40,000
Textbooks: $2,000 * 4 = $8,000
Room and board: $12,000 * 4 = $48,000
$40,000 + $8,000 + $48,000 = $96,000.
Next, calculate the opportunity cost. This is the loss of potential gain you could have made upon choosing this alternative. In this case, the amount of money lost by not working for your high school boss for four years.
$25,000 * 4 = $100,000.
Finally, add those together. $96,000 + $100,000 = $196,000.
The cost of attending four years of college, including the opportunity cost, is $196,000.