To convert kilograms to grams using the ratio \(1000\) grams \(= 1\) kilogram, you multiply the number of kilograms by \(1000\).
For \(2.75\) kilograms:
\[ 2.75 , \text{kilograms} \times 1000 , \text{grams/kilogram} = 2750 , \text{grams} \]
Therefore, \(2.75\) kilograms is equal to \(2750\) grams.