To convert pounds to kilograms, you can use the conversion factor that 1 pound is approximately equal to 0.453592 kilograms.
Using this conversion factor:
\[ 72 \text{ pounds} \times 0.453592 \text{ kg/pound} \approx 32.6576 \text{ kg} \]
Now, rounding 32.6576 to the nearest kilogram gives:
\[ \text{Rounded result} = 33 \text{ kg} \]
Thus, 72 pounds is approximately equal to 33 kilograms when rounded to the nearest kilogram.