Ask five students how many practice questions they need and you'll get five guesses: fifty, two hundred, "all of them." The honest answer is less satisfying and more useful — you need enough to expose every way the topic can be asked, plus a clean re-test. Past that point, more questions are just cardio.

Why the question is misphrased

"How many" assumes volume is the variable. It isn't — coverage is. Twenty questions that all ask the same definition test one thing once. Six questions that each hit a different angle — a definition, a scenario, a comparison, a worked problem, a common-trap distractor — test the topic six different ways. It's the same principle behind mixing MCQ and short-answer practice: different formats force different retrievals.

The other variable everyone forgets is separation. Fifty questions done in one sitting build same-day fluency that evaporates. Fifteen questions done twice, three days apart, build something that survives until the exam. If you need concrete timing, here's a spaced repetition schedule you can actually follow.

The stopping rule that actually works

What a week of this looks like

This is the loop LearnX runs for you automatically: it generates practice grounded in your course files, tracks what you miss, and keeps pulling you back to weak spots inside each Study Unit — so 'enough' stops being a guess. If you run the loop manually, the habit that makes it pay off is an error log that changes your next attempt.