Four resistors of 10.0 each are connected in parallel. A combination of four resistors of 10.0 each is connected in series along with the parallel arrangement. What is the equivalent resistance of the circuit?

Question

A)80.0
B)40.4
C)40.0
D)42.5

This is all I understand. Can you explain step by step and show how to get the answer?

1/R = 1/Ra + 1/Rb + 1/Rc +1/Rd
? = 1/10.0 + 1/10.0 + 1/10.0 + 1/10.0

Answer 1

well
1/Req= 4/10 or Req=2.5 ohms.

Now, add the 40 ohms in series, so Rtotal=42.5ohms