R12 = (R1*R2) / (R1+R2) = 600 / 50 = 12
R34 = R3 + R4 = 6
Rэкв = (R12*R34) / (R12 + R34) = 72 / 12 = 6
R12 = (R1*R2) / (R1+R2) = 600 / 50 = 12
R34 = R3 + R4 = 6
Rэкв = (R12*R34) / (R12 + R34) = 72 / 12 = 6