Sub A

Substance A has a density of 1.096 g/ml

We convert Liters of Substance A to grams of Sub A

1 Liter x 1.096g/ml x 10^3 ml/L = 1096 grams Substance A

20 Percent of Aqeous solution containing Sub A is Sub A... sooo...

1096 x 80% = 876.8 g Sub A

Now we convert Sub A grams to milligrams

876.8 g Sub A x 1000mg/1g = 876800 mg of Sub A

Now we divide Sub A by 200mg/dose = 4384 dose Units Sub A

Lets back up a minute and assume less than 100% yield..

876.8 x 40% = 350.72 g Sub A x 1000/200 = 1753.6 dose Units Sub A