Solving Variable Resistance Circuit: Ohm's Law

[Warrzie]

Homework Statement

"A circuit has a variable resistance (total 100 ohms) across which is a voltage drop of 12 V supplied by a battery. What must be its resistance if the voltage is to be A) 12V and B) 6.2V?"

Homework Equations

V=IR

The Attempt at a Solution

We haven't learned anything besides Ohm's Law for these equations, so I tried plugging in different values to try and dial in the answers, but it didn't work. Is there something I'm missing or am I being asked to solve for two unknowns? Hints appreciated.

 

[denverdoc]

Is that all you have? Diagram? I am assuming total resistance is 100 ohms so for 12 v you have 8.5 amps. Then for 12V, you need a resistance of 12/8.5 but I don't trust this answer. If its a serial pair of resistors where Rx and Ry are 100 ohms and you are being asked the voltage drop across Rx, i think the above is good.

 

[Warrzie]

Diagram

 

[denverdoc]

drawing a blank on the diagram, literally