Hallo,
100 % entspricht 12500 g
1 % entspricht 12500/100 g
0,2 % entspricht 12500/100*0,2 g = 25 g $${\frac{{\mathtt{12\,500}}}{{\mathtt{100}}}}{\mathtt{\,\times\,}}{\mathtt{0.2}} = {\mathtt{25}}$$
oder kurz: 12500*0,2% = 25 g
$${\mathtt{12\,500}}{\mathtt{\,\times\,}}{\mathtt{0.2}}\% = {\mathtt{25}}$$
Gruß radix