Final answer:
The total resistance of a circuit with two parallel resistors each of 250Ω and an additional series resistor of 300Ω is found to be 425Ω after calculating the equivalent resistance of the parallel resistors (125Ω) and adding it to the resistance of the series resistor.
Step-by-step explanation:
To calculate the total resistance of a circuit with two parallel resistors and an additional series resistor, we first find the equivalent resistance of the parallel resistors, and then add the resistance of the series resistor. Given two parallel resistors each with a resistance of 250Ω, their combined resistance Rp is calculated as 1/Rp = 1/R1 + 1/R2, which equals 1/250 + 1/250 = 2/250. Solving this gives an equivalent parallel resistance Rp of 125Ω. Then we add the resistance of the series resistor (300Ω) to find the total resistance Rtot, which is Rtot = Rp + R3 equaling 125Ω + 300Ω = 425Ω. Therefore, the total resistance of the circuit is 425Ω.