United States
Hong KongConversions
The exam assumes fluency in a small set: 5 mL to a teaspoon, 15 to a tablespoon, 30 to a fluid ounce, 454 g to a pound, 2.2 pounds to a kilogram, and the metric prefixes.
The shortest topic on the syllabus and the one that costs the most marks when it is shaky.
Volume
| Household | Metric |
|---|---|
| 1 teaspoon | 5 mL |
| 1 tablespoon | 15 mL |
| 1 fluid ounce | 30 mL |
| 1 L | 1000 mL |
A tablespoon is three teaspoons and a fluid ounce is two tablespoons. Knowing the relationships as well as the numbers lets you recover one you have blanked on.
Weight
| From | To |
|---|---|
| 1 pound | 454 g |
| 1 kg | 2.2 pounds |
| 1 g | 1000 mg |
| 1 mg | 1000 mcg |
| 1 kg | 1000 g |
Dividing by 2.2 to get kilograms and multiplying by 454 to get grams are the same conversion at different scales. Questions mix them, and a candidate who has learned only one has to derive the other under time pressure. Learn both directions of both.
Length
One inch is 2.54 cm. It appears in body surface area work and in device questions.
The prefixes
Kilo is a thousand times, milli is a thousandth, micro is a millionth. Every metric conversion in pharmacy is a shift of three decimal places, in one direction or the other.
That framing makes the metric side almost error-proof: you are only ever deciding which way to move the point and how many times.
How to make them automatic
Not by reading the table. By doing a hundred one-line conversions with a timer, until the answer arrives before the working does.
Ten minutes a day for two weeks does it, and it is the highest-return drill available for this exam.
Common questions
How many mL in a teaspoon?
5 mL. A tablespoon is 15 mL and a fluid ounce is 30 mL.
How do I convert pounds to kilograms?
Divide by 2.2. To get grams instead, multiply by 454.
What are the metric prefixes?
Kilo is a thousand times, milli a thousandth, micro a millionth - each shift is three decimal places.
How many inches to a centimetre?
One inch is 2.54 cm.
How do I make conversions automatic?
A hundred timed one-line conversions, ten minutes a day for two weeks.