To find out how much sugar is in 450 grams of white chocolate that is 57% sugar, you can use the following calculation:
\[ \text{Amount of sugar} = \text{Total weight} \times \text{Percentage of sugar} \]
In this case:
\[ \text{Amount of sugar} = 450 , \text{grams} \times 0.57 \]
Calculating this gives:
\[ \text{Amount of sugar} = 450 \times 0.57 = 256.5 , \text{grams} \]
So, there are 256.5 grams of sugar in 450 grams of white chocolate.