Knowing that I1 = 100mA, I3 = 300mA, UR2 = 10V, determine R2.
So I tried it like this: we know that in parallel connection, the voltage stays the same so UR2 = UR1 = 10V. Then, R1 = U1 / I1 = 100 Ohm. Also, I3 = I2 + I1 so I2 = 0.3A - 0.1A = 0.2A and so R2 = 10 / 0.2 = 50 Ohm.
Is this correct? I'm trying to learn for the exam but something doesn't seem right to me here.