Probability & reasoning
Probability Trainer
Timed probability drills inspired by real trading-firm interviews: counting, conditional & Bayes, expected value and logic puzzles. Tune the difficulty, topics and pace, then track your accuracy and speed.
Settings
Save3 minutes
1 min15 min
Performance
This combinationhighest accuracy
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attempts
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Track your best scores and watch your accuracy climb across every session.
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Last 30 days| 1 | SiarheiHumbar | 6 / min |
| 2 | AlgoCurve | 5.7 / min |
| 3 | DeltaDelta | 5.3 / min |
| 4 | Mstatix | 5.3 / min |
| 5 | BearishEdge | 5 / min |
| 6 | SwiftRaptor | 5 / min |
| 7 | OliS | 5 / min |
| 8 | StochasticEdge | 4.3 / min |
| 9 | NimbleScalper | 4 / min |
| 10 | NeutralOption | 4 / min |
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Frequently asked questions
How does the Tradermath Probability Trainer work?
The Tradermath Probability Trainer presents you with probability questions inspired by real trading-firm interviews and asks you to solve them. You can adjust difficulty, time limits, topic categories and question types to customise your training exactly how you want.
What's the difference between the topic categories?
Each category targets a different skill. Counting & Combinatorics covers permutations, arrangements and sampling. Conditional & Bayes covers Bayes’ theorem and conditional probability. Expected Value covers E[X], averages and order statistics. Logic Puzzles covers numerical reasoning, rates and spatial puzzles.
How often should I train?
Consistency beats long sessions. Train at least 3 to 4 times a week for 10 to 20 minutes. Daily practice is ideal for building strong probability intuition, and short focused sessions help you retain concepts better than occasional marathons.
Should I use open questions or multiple choice?
Open questions are much harder and build deeper understanding because you must work through the problem completely. Multiple choice is faster and trains elimination skills (spotting and removing wrong answers), which is valuable in timed tests. Mix both for well-rounded preparation.
How can I improve my probability solving speed?
Start with easier difficulties to build confidence, then gradually increase. Focus on the underlying patterns and formulas, and practise recognising question types quickly so you can apply the right approach immediately. Aim for at least 90% accuracy at your current level before making it harder.