Series: $$ Z_T = Z_1 + Z_2 + ... + Z_N $$ $$ I = \frac{E}{Z_T} $$
Voltage divider rule:
$$ V_x = \frac{Z_x}{Z_T}E $$
Parallel: $$ Y_T = Y_1 + Y_2 + ... + Y_N $$ $$ Z_T = \frac{Z_1Z_2}{Z_1+Z_2} $$
Current divider rule:
$$ I_1 = \frac{Z_2}{Z_1+Z_2}I_T $$
$$ I_2 = \frac{Z_1}{Z_1+Z_2}I_T $$