Connecting in series : equivallent resistance R is the sum of resistances : R = r

Connecting in parallel : the equivallent conductance 1/R is the sum of conductances : 1/R = 1/r

We want an equivallent resistance of 30 Ω by connecting two resistors with **integral** values in parallel.

Give all possibilities for the two resistors values.

Solution

Is it possible to use resistors from the normalized set
E12 = {10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82} and
10^{± n} multiples

Solution