Free sequences and probability practice test
60 typed-answer questions in 10 minutes: +1 per correct answer, −1 per wrong answer, skips free. The questions cover number-series patterns and quick probability and expected-value calculations, two skills that appear in almost every trading-firm assessment. The format is generic and not tied to one firm. TradeMind practice target: 40 net on this 60Q / 10-minute set (not a firm cutoff). Free, with no signup. The set is fixed: same questions, same order, every time.
60 questions · 10 minutes · typed answers
+1 per correct answer, −1 per wrong answer, skips are free. Number-series pattern recognition and quick probability/EV calculation, with typed answers. TradeMind practice target: 40 net on this 60Q / 10-minute set (not a firm cutoff).
What this test covers
Almost every trading-firm online assessment includes these two question families alongside arithmetic: finding the pattern in a number series, and computing a probability or expected value quickly. Optiver, Jane Street, SIG, and many others test both, so this simulator is a standalone practice format rather than a reconstruction of one company's test.
| Length | 60 questions · 10 minutes (10 seconds per question) |
|---|---|
| Input | Typed answers (open input, not multiple choice) |
| Scoring | +1 correct · −1 wrong · 0 skipped |
| Content | Number sequences · dice & card probability · expected value |
Reading a sequence fast
Start by writing out the differences between consecutive terms. If they are constant, the series is arithmetic: add that constant to the last term. If the second differences are constant, it is a quadratic-feel series: extend the difference pattern one step, then add it. If consecutive terms have a constant ratio, it is geometric. If each term is the sum of the two before it, it is Fibonacci-style. Checking these four cases in order is faster and more reliable under time pressure than trying to spot the pattern by eye.
Probability under time pressure
Most of these questions reduce to counting: matching outcomes divided by possible outcomes. Two-dice sums follow a fixed table worth memorising (7 is the most common sum, with 6 of 36 combinations; 2 and 12 are the rarest, with 1 each). Expected value is a weighted average: multiply each outcome by its probability and add. Speed comes from knowing these results instead of re-deriving them, as multiplication tables save time over repeated addition.
Questions
Is this based on one specific firm's test?
No. Unlike this site's other simulators, Sequences & Probability does not reconstruct any single firm's assessment. Number-series pattern recognition and quick probability/EV calculation appear in some form in almost every trading-firm online test, so this is a generic practice format for both skills rather than a copy of one company's question bank.
What kinds of sequences show up?
Arithmetic (constant difference), geometric (constant ratio), quadratic-feel series (constant second difference), Fibonacci-style (each term is the sum of the two before it), and alternating-step patterns (add, subtract, add, subtract). Every sequence gives five or six terms and asks for the next one.
What kinds of probability questions show up?
Two-dice sum probabilities, expected value of a die roll with a payout multiplier, coin-flip run probabilities, card-draw probabilities from a standard deck, expected value of a simple win/lose bet, and "at least one" / "none at all" probabilities over several die rolls.
Should I answer as a decimal or a fraction?
Either. Typing 5/36 or 0.1389 both grade as correct for a probability question, and whole numbers or clean decimals work for expected-value questions. Every answer is typed; there is no multiple choice.
Is there an official pass mark?
No. The format is not tied to a specific firm, so there is no firm cutoff to report. TradeMind practice target: 40 net on this 60Q / 10-minute set (not a firm cutoff).
TradeMind is an independent training tool and is not affiliated with, endorsed by, or sponsored by any firm mentioned elsewhere on this site. This simulator is a generic practice format for number-series and probability/EV questions, not a reconstruction of any specific firm's assessment. Question content is procedurally generated and does not reproduce actual test material.