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Mental math drills

Case math is mostly percentages, growth and big numbers, done fast and out loud. Warm up here before a case.

Choose a drill

Topic

Length

10 questionsUntimed per question; accuracy counts. 2-minute sprintAs many as you can before time runs out.

Type answers like 168, 25%, 1.44B or 60,000. Answers within about 1% count (a little more for "roughly" questions).

Round complete

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Built by Luca Murri. All cases are original and all numbers are illustrative.

Code: MIT license · Case content: CC BY-NC 4.0 · No accounts, no tracking — your progress stays in your browser.