ad_astra

R = V/I V= IR I= V/R it depends what kind of circuit it is, if its a series or parallel. with resistors in series you just add their resistances together. R(total) = R1 + R2 + R3... etc. for resistors in parallel:- 1/R(total) = 1/R(1) + 1/R(2) + 1/R(3) so if R1 = 8 ohms and R2 = 8 ohms and R3 = 4 ohms 1/R(total) = 1/8 + 1/8 +1/4 = 1/2 1/2 is the reciprical so flip it over to get 2/1 and therefore the total resistance = 2 ohms. hope tha makes sense?