What is the resistance of a circuit if it draws 300 milliamperes from a 3-volt battery?

To calculate the resistance using Ohm's Law (R = E / I), you must first ensure all measurements are in their standard base units. The voltage is already given in standard units (3 volts), but the current is given in milliamperes. Convert 300 milliamperes to amperes by dividing by 1,000, which gives you 0.3 amperes. Now, plug these standard values into the Ohm's Law formula: R = 3 V / 0.3 A. Dividing 3 by 0.3 yields exactly 10 ohms. If you fail to convert the units first, you might incorrectly divide 3 by 300, leading to a mathematically incorrect answer for this circuit.