Average a list of percentage scores.
Percentages can be averaged directly only when each one represents the same amount of work — five quizzes all marked out of the same total, for example. Add the values and divide by how many there are. Where the assessments differ in size, averaging the percentages is wrong and you need the underlying points instead. The spread figure is the honest companion to the mean: a 80% average built from 78, 80 and 82 is a very different picture from one built from 55, 85 and 100.
Average of a percentage list
Average = sum of percentages / count of percentages
Only if every score is out of the same total. Averaging 90% on a 10-point quiz with 60% on a 200-point exam gives 75%, but the true combined score is 61.4% — the exam dominates. Use points, not percentages, when the totals differ.
The toggle sorts your list, removes the single smallest value and averages what remains. Many syllabi allow exactly one drop, which is why the count of scores actually used is reported alongside the average.
Commas, semicolons, spaces or line breaks all work. Anything that is not a number is ignored, so a trailing comma or a stray label will not break the result.