Explanation:

- Two resistors R1 and R2 are in parallel.

- They are made of the same material and have the same thickness.

- Length of R2 is twice the length of R1.

- Resistance is directly proportional to length if material and thickness are constant.

- So, R2 = 2R1.

- In parallel, the total resistance \( R \) is given by \( \frac{1}{R} = \frac{1}{R1} + \frac{1}{R2} \).

- Simplifying gives \( \frac{1}{R} = \frac{1}{R1} + \frac{1}{2R1} = \frac{3}{2R1} \).

- Hence, \( R = \frac{2R1}{3} \).

Correct statement: 3R = 2R1.

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