PRACTICE GUIDE MAKO
Mako Round Two: what the test is, and how to train for it
The Mako round two screen is 28 questions in 30 minutes - about 64 seconds each - answered by picking one of the options. There is no negative marking, so leaving an item blank gains you nothing over guessing.
Where it sits: Round two. The practice sitting on this page runs the same item count, the same clock and the same marking rule, with questions generated by Outcry rather than taken from Mako.
Outcry is not affiliated with Mako and has no access to their assessment content. This guide describes an assessment format that candidates report publicly; the questions here are generated by Outcry and are not Mako’s own.
What it screens
A derivatives market maker founded in London, trading options and futures across global exchanges.
- ✓Expected value computed fast and used to make a decision
- ✓Conditional probability and Bayes updates without formal notation
- ✓Ranking likelihoods rather than computing them exactly
- ✓Fermi estimation: decomposing an impossible question into three easy ones
Where it sits at Mako
This section does not arrive on its own. It closes the paper, and the sitting around it runs 45 minutes and 65 items in total, with Aptitude test on the same continuous clock. Candidates who prepare only for this round tend to be caught by the pacing of the rest.
There is no going back. You answer or skip, and the next item loads, which means the decision to leave an item is final at the moment you make it.
The format
These are the numbers the Mako sitting on this site runs on, matching the format candidates report.
| Questions | 28 |
|---|---|
| Time | 30 minutes |
| Per question | 64 seconds |
| Negative marking | No |
| Answer style | Multiple choice |
| Where it sits | Round two |
What it tests, with a worked example
Every example below is generated by Outcry, drawn from the same question generators the timed drills run. None of them is Mako’s.
Expected value and odds
Pricing a bet, converting between odds and probabilities, and deciding whether to take it.
Example
You roll a fair die 3 times. Probability of at least one six?
- 50%
- 32.1%
- 42.1%
- 0.5%
Answer 42.1%
Complement: 1 − (5/6)^3 = 42.1%. Adding 1/6 each time double-counts.
Conditional probability
Bayes' rule in disguise: a test result, a signal, a drawn card, and what it implies.
Example
A strategy's daily returns over n days average x̄ with sample standard deviation s. Which statistic tests whether the true mean return is zero?
- x̄ / (s/√n)
- x̄·√n / s²
- (x̄ − s) / n
- x̄ / s
Answer x̄ / (s/√n)
The one-sample t-statistic divides the observed mean by its standard error s/√n. Dividing by s alone ignores how the estimate sharpens with n.
Distributions you should know cold
Binomial, geometric and uniform means and variances, applied rather than quoted.
Example
Two return series correlate at 0.5. What share of the variance in one is explained by a linear fit on the other?
- 100%
- 75%
- 25%
- 70.7%
- 50%
Answer 25%
R² is the square of the correlation: 0.5² = 0.25, so 25%.
Ranking outcomes
Ordering several events by likelihood, where only the exact order scores.
Example
An index fund charges 5 basis points a year and keeps 3.0% of assets in non-interest-bearing cash. The index returns 6.0% over the year. What is the tracking difference in basis points, as a signed number?
Answer -23
Tracking difference is the fund's return less the index's. The invested 97.0% earns the index return and the cash earns nothing, so the drag is 3.0% x 6.0% = 0.1800%, or 18.00 basis points. The fee takes another 5 basis points. Together the fund returns 6.0% - 0.05% - 0.1800% = 5.7700%, a tracking difference of -23.00 basis points. Cash drag hurts in a rising market and the fee is the only part that costs the same whatever the market does. Tracking difference is the realised gap; tracking ERROR is the volatility of that gap and is a different number.
Waiting times and repeated trials
How long until the first success, and why the answer is rarely the average you expected.
Example 1
How many digits does 50! have?
Answer 65
Stirling: log10(50!) ≈ 50·log10(50/e) + ½·log10(2π·50) = 63.23 + 1.25 = 64.48, so 65 digits.
Example 2
How many observations are needed for a 95% confidence interval of half-width 2.5, when the standard deviation is 25?
Answer 385
n = (1.96σ/w)². Call it 2: (2 × 25/2.5)² = 400, which overshoots by 4%.
Example 3
A trading floor has 40 people on it. What is the chance that at least two share a birthday, as a percentage?
Answer 89
There are C(40,2) = 780 pairs, each matching with probability 1/365. P(none) ≈ e^−2.14 ≈ 0.12, so about 88%.
Reading the question exactly
At least, exactly, and given that - the three phrases that change the answer entirely.
Example
A puts in 3,000 for 4 months and B puts in 13,000 for 9 months. They clear 33,000 of profit. What is A's share?
- 16,500
- 10,153.85
- 6,187.5
- 3,069.77
Answer 3,069.77
Profit follows capital multiplied by time. A contributes 3,000 x 4 = 12,000 and B contributes 13,000 x 9 = 117,000, so A takes 12,000 / 129,000 of 33,000 = 3,069.77.
What a good score looks like
On a paper of 28 questions with no penalty for a wrong answer, the only thing an unanswered question can do is cost you. Probability rounds are usually marked as part of a wider battery, so a standalone threshold is rarely reported. Where candidates do describe one it clusters around getting two thirds of the items right, with the caveat that these sections are short enough that two mistakes move you a long way.
How to train for it
- 01Work the standard results until they are recall, not derivation: complement, conditional, binomial mean and variance, geometric expectation.
- 02Practise setting up before calculating. Most wrong answers on these are a correct calculation of the wrong quantity.
- 03Work the complement first whenever the question says at least or at most. It is usually the shorter route and it is almost always the intended one.
TRAIN IT HERE
The drills that match each section
Likelihood Ranking
Order events from most to least likely - the exact screen-question format.
Fermi Estimation
Piano tuners in Chicago, atoms in a body - scored on order of magnitude.
Quitters Never Lose
A casino stopping-strategy game that is secretly a martingale lesson.
Tail Risk
Rare events and fat tails, and what they do to a plain expected-value estimate.
SIT THE FULL BATTERY
All the sections back to back on one clock, marked the way the real screen marks them, with a by-skill breakdown at the end. Included with any pass.
Also reported at Mako
Common questions
- Is the Mako round two test multiple choice?
- Multiple choice. You pick one option per question.
- How long is the Mako round two test?
- 28 questions in 30 minutes, which is about 64 seconds each.
- Is there negative marking on the Mako round two test?
- No. A wrong answer costs nothing beyond the mark you would have earned, so leaving an item blank is never better than guessing at it.
- How do I practise for it free?
- Every drill linked on this page is free to play, with no account, inside a daily run cap. Questions are generated fresh each run, so there is nothing to memorise between attempts. The full Mako Aptitude and Round Two sitting puts the sections back to back on one clock.