What is the total resistance of four 68-ohm resistors wired in parallel?

To find the total resistance of identical resistors in parallel, you divide the resistance of a single resistor by the total number of resistors in the circuit. The formula is R_total = R / n. Here, you have four resistors that each have a value of 68 ohms. Dividing 68 by 4 gives a total equivalent resistance of 17 ohms. If you simply multiplied 68 by 4 to get 272 ohms, you would be calculating the value for a series circuit, not a parallel one. Remember that adding resistors in parallel always decreases the total resistance.