The number of milligrams of drug that are in 45 ml of a 1.5% w/v solution
is 0.675 mg
calculation
this is calculated using ( %M/V = mass in milligrams/ volume x100 formula )
%M/V = 1.5 %
volume = 45 ml
mass = ?
convert %(m//v) into fraction = 1.5/100 and let the mass be represented by y
therefore 1.5/100 = y/45
cross multiplication
=67.5 = 100 y
divide both side by 100
y=0.675 mg