If you dissolve 20 g of a drug in 250 ml of water, what is the percentage strength (w/w)?
My answer:
(20 g/250 ml) = (x/100 ml)
x= 8%
looks good
w/w is weight to weight ... water is 1 g per ml , so the numbers work
... 20 g / 250 g = .08 = 8%