The resistance of a parallel circuit with 3 bulbs is 1/ 1/R₁ + 1/R₂ + 1 /R₃ .
b. The resistance of a parallel circuit with 3 bulbs is 1.5 ohms. Find the resistances of the bulbs, if two of them have equal resistances, while the resistance of the 3rd is 3 ohms less.