How many milliliters of an injection containing 0.25 mg of drug in each milliliter should be administered to provide a dose of 10 mcg?

How many milliliters of an injection containing 0.25 mg of drug in each milliliter should be administered to provide a dose of 10 mcg?

Answer

0.04 millilitre

Explanation

1 milligram (mg) = 1000 micrograms (mcg)
0.25 mg of drug in a millilitre is equivalent to (0.25 * 1000) mcg = 250 mcg
250 mcg = 1 millilitre
10 mcg = x millilitre
x = 10 * 1 / 250 = 0.04 millilitre
The injection needed is 0.04 millilitre