One milligram is .000001 kilograms.
1.2 kg = 1200 mg
250,000,000
0.51 kg = 510,000 milligrams.
Since there are 1000 mg in 1 gram, and 1000 g in 1 kg, there are (1000 x 1000) mg in 1 kg, which is 1,000,000 mg in 1 kg. Or conversely, there are 0.000001 kg in 1 mg (that's 10-6 kg)
1 kg = 1000000 mg
1000 mg = 1 g; 1000 g = 1 kg, therefore 1000 x 1000 or 1 000 000 mg/kg
1 mg/kg = 1 ppm 1 mg = 1000 micrograms (ug) so 10 ug/kg = 0.01 mg/kg = 0.01 ppm
cc = ml if you assume that density is 1 g / ml, you assume a gram is a millilitre then 300 mg / ml = 300,000 mg per kilogram
7 kg is 7,000,000 mg
1 milligram = 1.0 × 10-6 kilograms
230 mg = 0.00023 kg
1 kg = 1 000 000 mg 5 000 841 mg = 5.000841 kg = 5 kg (approximated to 2 decimal points)