To convert 35 pounds to kilograms using the ratio of 1 pound equals about 0.45 kilograms, you can use the following calculation:
\[ \text{Kilograms} = \text{Pounds} \times 0.45 \]
\[ \text{Kilograms} = 35 , \text{pounds} \times 0.45 , \text{kg/pound} \]
\[ \text{Kilograms} = 15.75 , \text{kg} \]
Therefore, the answer is 15.75.