How Flow Traders's process runs, as candidates and the firm describe it, and the questions candidates report, each with a worked solution. Free, no sign-up.
Candidates report a mental maths test with no scratch work (estimation matters), a recruiter screen with probability questions, then technical rounds with quick arithmetic and probability, including poker odds.
Try each one before opening the solution. Interviewers change the numbers, so learn the method.
Trader Intern · Technical · Probability · reported by a candidate
Reported: "what is the probability of winning a Texas Hold'em hand post-flop?" Here is a concrete version you should be able to do in your head.
Practice (ours): after the flop you hold a flush draw (9 outs among 47 unseen cards). What is the probability of completing it by the river (two more cards)? (our follow-up)Answer and worked solution
Answer: 0.34968
Key idea. Easier via the complement: miss on both the turn and the river.
Turn: 38 of 47 unseen cards miss.
River: 37 of 46 miss.
P(miss both) = (38/47)(37/46) ≈ 0.650.
P(hit) ≈ 0.350.
Check. Rule of 4: outs × 4 ≈ 9 × 4 = 36%. Close.
Trap. Adding 9/47 + 9/46, which double-counts hitting on both cards.
Interviewers may push further: With 9 outs and one card to come? (≈ 9/46 ≈ 0.196; rule of 2 gives 18%.)
Graduate Trader · Interview · Logic · reported by a candidate
100 pounds of watermelon is 99% water. After drying in the sun it is 98% water.
How much does it weigh now (pounds)?
Answer and worked solution
Answer: 50
Key idea. Track what doesn't change: the non-water mass.
Before: 1% of 100 lb = 1 lb of non-water.
After, that 1 lb is 2% of the total.
Total = 1/0.02 = 50 lb.
Trap. Answering 99 lb ("it lost 1% of its water").
Interviewers may push further: The same report had the torch-and-bridge puzzle: four people take 1, 2, 5 and 10 minutes; at most two cross at once with one torch. Get everyone over in 17 minutes. (1+2 over, 1 back, 5+10 over, 2 back, 1+2 over.)
Trader · Interview · Behavioural · reported by a candidate
Behavioural questions candidates report:
Why trading, and how did you discover it? Why Flow Traders?
Tell me about a time you took initiative.
In your own words, how does Flow Traders make money?
What is arbitrage? Give an example.
Answer one out loud, as you would in the interview.
Model answer
Three parts, about a minute each. Why trading: a specific moment you got hooked (a game, a market you followed, a decision under uncertainty), not "I like maths". Why this firm: something concrete about how it trades or trains people, ideally from talking to someone there or from its own material. Why you: evidence you already think in probabilities and react well to being wrong. Avoid anything about money or prestige.
For the others: Use a short story: the situation in one sentence, what you did (not the team), the result with a number if you have one, and what you'd do differently. Aim for about two minutes.
How a market maker earns: it quotes both sides and earns the spread, hedges what it accumulates, and is paid for providing liquidity, mostly in ETFs for Flow Traders. Arbitrage: locking in a riskless profit from a price difference, e.g. an ETF trading above the value of its holdings: sell the ETF, buy the basket, create units.