Electricity doesn't travel at a constant speed like light does. The speed of electricity depends on the medium it's traveling through and the characteristics of the conductor.

Here's why it's not a simple calculation:

* Speed of Light: In a vacuum, electricity travels at the speed of light, which is approximately 186,282 miles per second or 299,792,458 meters per second. This is about 11.8 inches per nanosecond.

* Conductors: In electrical wires, the speed is slower due to resistance and other factors. The speed can be significantly less than the speed of light.

* Signal Propagation: It's important to distinguish between the speed of light and the speed of signal propagation. The speed of light describes the movement of electromagnetic waves, while signal propagation refers to the speed at which information travels along a conductor.

* Signal Velocity: The signal velocity in a conductor can be calculated using a formula involving the conductor's inductance, capacitance, and resistance. It often falls in the range of 50% to 90% of the speed of light.

In summary: While the speed of light in a vacuum is approximately 11.8 inches per nanosecond, the actual speed of electricity in a conductor can vary significantly and is often much slower.