To convert pounds to kilograms, you can use the conversion factor that 1 pound is approximately equal to 0.453592 kilograms.
To convert 100 pounds to kilograms:
\[ 100 , \text{lb} \times 0.453592 , \text{kg/lb} \approx 45.3592 , \text{kg} \]
So, 100 pounds is approximately 45.36 kilograms.