Given that,
Difference between series and parallel combinations of resistors.

Resistors in parallel $\frac{1}{{\mathrm{R}}_{\mathrm{eq}}}=\frac{1}{{\mathrm{R}}_{\mathrm{x}}}+\frac{1}{{\mathrm{R}}_{\mathrm{y}}}+\frac{1}{{\mathrm{R}}_2}$

∴ equivalent resistance in Parallel combination :

${\mathrm{R}}_{\mathrm{eq}}=\frac{{\mathrm{R}}_{\mathrm{x}}{\mathrm{R}}_{\mathrm{y}}{\mathrm{R}}_{\mathrm{z}}}{{\mathrm{R}}_{\mathrm{x}}{\mathrm{R}}_{\mathrm{y}}+{\mathrm{R}}_{\mathrm{y}}+{\mathrm{R}}_{\mathrm{z}}+{\mathrm{R}}_{\mathrm{z}}·{\mathrm{R}}_{\mathrm{x}}}$

In each resistor when connected in parallel, the current is different but the Potential difference is same.
I_T = I₁ (leresistance) +
I₂ (Ryresistance) +
I₃ (Rzresistance)

V = V_Rx = V_Ry = V_Rz

Resistars in series R_eq = R_x + R_y + R_z.

Equivalent resistance in series combination :

R_eq = R_x + R_y + R_z

In each resistor when connected in series, the current is same but Potential difference is different.
I = I_Rx = I_Ry = I_Rz
V = V_Rx + V_Ry + V_Rz