Question

What is the equivalent resistance?​

Answer 1

C 3.33 Ω

Step-by-step explanation:

From the equation given 1 / Rtot = 1/10 + 1/5 = 3/10

then Rtot = 10/3 = 3.33 Ω

As an aside:

When there are only two resistors in parallel, the equivalent R is

= R1*R2 / (R1 + R2) = 10*5 / (10+5) = 50 / 15 = 3.33 Ω