Common mistake
Treating mean, median and 'average' as one number
It sounds like this
“Mean, median, average — they're all just different words for the same thing.”
Why it’s wrong
It hides that the two are worked out differently, so it never occurs to them that the two numbers can be far apart.
The lesson that fixes it
Cognosc spots mistakes like this.
When you explain something in your own words, Cognosc can tell exactly which mistake you’re making — not just that you’re wrong — and gives you a short lesson to fix that one thing.