Hello,
(i) Express n as the subject.
[tex]C=\frac{nA}{n+12}[/tex]
[tex]C(n+12) = nA\\nC + 12C = nA\\\frac{nC+12C}{n}=\frac{nA}{n} \\\frac{nC}{n}+\frac{12C}{n} = A \\\frac{12C}{n} =A-C\\\frac{n}{12C}=\frac{1}{A-C} \\n = \frac{12C}{A-C}[/tex]
(ii)
Since C = 6 mL and n = 8 we need to solve this equation of unknown A :
[tex]6 = \frac{8A}{8+12} \\6 = \frac{8A}{20}\\8A = 20*6\\A = \frac{5*4*2*3}{4*2}\\A = 15[/tex]
Thus, the equivalent adult dosage A would be 15 mL
(iii) I let you think about this one
Good Luck
