Hi Rusty,

1/R total= 1/R1 + 1/R2 ..... + 1/Rn

Sum of the inverses.

For example: a 100 and 200 ohms resistor gives

1/R total = 1/100 + 1/200 = 2/200 + 1/200 = 3/200

R total = 66.67 ohms Login to read more.