If resistors of 8/9 Ω, 4/3 Ω, and 2/3 Ω are connected in a star configuration, what are the values of their equivalent delta-connected resistors?

Using Star-to-Delta conversion: for star resistances $R_A = \frac{8}{9}\,\Omega$, $R_B = \frac{4}{3}\,\Omega = \frac{12}{9}\,\Omega$, and $R_C = \frac{2}{3}\,\Omega = \frac{6}{9}\,\Omega$. The product sum is $\Sigma = R_A R_B + R_B R_C + R_C R_A = \frac{96 + 72 + 48}{81} = \frac{216}{81} = \frac{8}{3}$.

Delta resistors are: $R_{AB} = \frac{\Sigma}{R_C} = \frac{8/3}{2/3} = 4\,\Omega$; $R_{BC} = \frac{\Sigma}{R_A} = \frac{8/3}{8/9} = 3\,\Omega$; $R_{CA} = \frac{\Sigma}{R_B} = \frac{8/3}{4/3} = 2\,\Omega$.

Option Analysis: