Explanation:
Calculate the dosage by converting grains to
milligrams:
1 gr/60 mg = 0.5 gr/X.
X= 30 mg.
Then, use the ratio-and-proportion method to determine the number of
milliliters to administer:
15 mg/1 ml = 30 mg/Y.
Y = 30 mg x 1 ml/15 mg = 2 ml.