A patient is prescribed 0.210 mg of a drug that is available in 70 μg tablets. How many tablets are needed? (Remember that the number of significant figures does not matter because the number of tablets is being counted.)
To determine the number of tablets needed, we need to divide the prescribed dosage by the dosage per tablet. Here's how you can perform the calculation:
Step 1: Convert the prescribed dosage from milligrams to micrograms.
- Since there are 1,000 micrograms (μg) in 1 milligram (mg), multiply the prescribed dosage by 1,000 to convert it to micrograms.
- 0.210 mg * 1,000 μg/mg = 210 μg
Step 2: Divide the prescribed dosage in micrograms by the dosage per tablet.
- Divide the prescribed dosage (210 μg) by the dosage per tablet (70 μg).
- 210 μg ÷ 70 μg/tablet = 3 tablets
Therefore, you need 3 tablets to fulfill the prescribed dosage of 0.210 mg.