mental-math
A timed arithmetic drill that records every answer.
Ready when you are
80 questions in 8 minutes
Edit 80 questions · 8:00
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What this is
Several trading firms screen candidates with a fast, no-calculator arithmetic test
before any interview. This does not reproduce any firm's assessment — the widely
circulated 80 questions in 8 minutes format turns out to have
no firm-published source at any of the six firms checked.
What it reproduces is the constraint: far more questions than there is time to
answer carefully. The sourced findings are in
RESEARCH.md.
Enter a whole number, a decimal, or a fraction —
36, 0.375, 3/8 and -12.5 all work.
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by category
| category | n | acc | think | total |
|---|
think is the median time from seeing the question to your first keystroke — the arithmetic itself. total also includes typing the answer. The gap between them is measurement overhead, not skill.