What is the equivalent of 1 pound in kilograms?

The equivalence of 1 pound in kilograms is precisely 0.454 kilograms. This conversion factor is derived from the exact definitions of the pound and kilogram in the metric system, where 1 pound is defined as approximately 0.45359237 kilograms. Therefore, for practical purposes, it is commonly rounded to 0.454 kg. This understanding is essential for mass and balance calculations, particularly in aviation, where precise weight measurements are critical for safety and performance considerations.

The other options do not accurately represent the conversion from pounds to kilograms. For example, 1 kg is significantly more than 1 pound, and both 0.205 kg and 2.2 kg deviate from the correct conversion factor. Hence, recognizing 0.454 kg as the correct equivalent is crucial in contexts requiring accurate conversions between mass measurements.