Under what circumstances are we fair in this classical dorm situation? So I am going to college this fall. I had two roommates sharing the same room. I will bring the fridge, $\$150$, jack will bring a TV, and Kyle will bring a printer. The TV and the printer are of the same value, let us call its dollar value $x$. So all three of us are using the fridge, so each is paying $\$50$. However, I will not be using the TV Jack has brought, but I will be using the printer Kyle brought. But Kyle and Jack will use all three things.
My question is how much will I have to pay for the printer and pay to whom for it will make it fair?
First attempt: Suppose I do not use anything else except the fridge which I have already paid for $\$50$. Say now I want to use the printer too, I will pay $\frac{x}{3}$ dollars to Kyle, so we will be fair because kyle had the printer.
Second attempt: Suppose I do not use anything else except the fridge which I have already paid for $\$50$. Say now I want to use the printer too, I will pay $\frac{x}{6}$ dollars to Kyle and $\frac{x}{6}$ to jack, so we will be fair. Because in this case I view the (printer and the TV) belongs to both jack and kyle, so jack and kyle both have shares in the printer now.
Any thoughts? I am really confused.

Your first attempt is closer.  Usage of the TV should cost $x/2$ because there are only two people using it.  You and Jack should pay $x/3$ to Kyle for the fridge, but Kyle should pay $x/2$ to Jack for the TV.  They should each pay you 50 for the fridge.  If you want, you can net things out, but it may be easier just to make these payments.  
Your second attempt works, too.  In the first, you are buying into the printer at the start, when Kyle owns it.  He will also get $x/3$ from Jack.  In the second, Jack has paid Kyle $x/2$ because you initially did not want to use the printer.  You now need to buy a one-sixth share from each of them, which you are doing.
