Use the formula: 1 / Rtotal = 1 / R1 + 1 / R2 + 1 / R3 + …
Find the reciprocal of each resistance
Add all the reciprocals together
Take the reciprocal of the sum to get the total resistance
For two resistors, use: Rtotal = (R1 × R2) / (R1 + R2)
For identical resistors, use: Rtotal = R / n
Keep the total resistance less than the smallest individual resistance in the parallel circuit