Rounding — drug calculations
Rounding in drug calculations
When to round, how many decimal places to give and what applies to drops and tablets.
Round last
Do not round intermediate results, only the final answer.
Drops cannot be divided, so the answer is about 42 drops/min.
Things to remember
Read what is asked for
Does the question state a number of decimal places or a unit?
Whole units where required
Drops and tablets are not given in fractions, unless the tablet is designed to be divided. See tablets.
Sense-check first
Ask yourself whether the answer could actually be measured out in real life.
Keep the decimals in your calculator
Use the memory function instead of rounding by hand.
Frequently asked questions
Should you round during the calculation?+
No, round last. Otherwise the errors can grow.
How many decimal places should I give?+
It depends on the question and your course. Read what is asked for.
How do you round drops?+
Drops are whole units. 41.7 drops per minute is usually given as 42.
Can you split tablets?+
Only if they are designed for it. See the page on tablets.
Practise rounding correctly
Practise questions where the rounding decides the answer. The calculator sits next to the question, so you work the way you would in an assessment.
