Three identical resistors are connected in parallel. If one of the resistors is disconnected and connected

Three identical resistors are connected in parallel. If one of the resistors is disconnected and connected in series with the other two, then the resistance of the circuit increases by 700 ohms. What is the resistance of each resistor?

Let’s designate the resistance of the first version of the circuit through R1, and the second by R2.
Then

R1 = R / 3;

R2 = R / 2 + R.

The difference in resistance is known. Let’s make the equation

R2 – R1 = 700;

(R / 2 + R) – R / 3 = 700.

Let’s transform and find the resistance of one resistor

(3R – 2R) / 6 + R = 700;

R / 6 + R = 700;

(R + 6R) / 6 = 700;

7R = 6 * 700;

R = 6 * 700/7 = 600 ohms.

Answer: The resistance of each resistor = 600 ohms.