Also remember that 1 hour of work also has the extra time you need to feed yourself (so 1 hour lunch for 8 hours work), and you need to add the sleep time (you sleep about 1-1 so 8 hours sleep for 8 hours of work) and the down time. A better approximation is just taking the time and multiplying it by 3 or 4, since we work 1/3 of the time, and you can look at the other time in your day as simply supporting and recovering for your work time. Unless you have flexible hours, then you can literally pick up another hour of work to pay for a meal out.