Training
Timed sprints for arithmetic, squares and case math — plus flashcards with spaced repetition when you want to go slower. History stays in this browser.
Addition, subtraction, multiplication and division against the clock. Answers are always whole and never negative.
Memorize the squares table. Numbers you miss or have to work out come back more often than the ones you already know.
The arithmetic behind estimates and case interviews: big products, percentages, fractions, growth rates and one-step market sizing. Estimates are graded within a tolerance — press Enter to submit those.
Decks with spaced repetition. Flip, type the answer, or cram the whole set.