Equity Research puzzles, solved step by step

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071A timed aptitude item of the kind used on Wonderlic-style tests: if 3 analysts write 3 reports in 3 days, how many reports do 9 analysts write in 9 days?Data and reasoning trapsWarm upPoint72New York · 2026
Try it first
Answer inside ten seconds.
Show the worked solution
27 reports. Find the unit rate first: 3 analysts writing 3 reports in 3 days means one analyst writes one report in 3 days, a third of a report per analyst-day. Nine analysts working nine days put in 81 analyst-days, and 81 x 1/3 = 27. Tripling the team triples the output and tripling the time triples it again: 3 x 3 x 3 = 27.
Why does the fast answer of 9 feel right?
The sentence has a rhythm, three, three, three, then nine and nine, and the ear wants to finish the pattern with another nine. It is the same pull as a kitchen puzzle where three cooks bake three cakes in three hours. Matching the pattern of the words is the trap; the fix is to reduce the problem to one worker and one day before scaling anything. Once you have the rate per analyst-day, the answer is multiplication.
The question's case, 3 analysts for 3 days, is 9 analyst-days and 3 reports, so one report takes 3 analyst-days; the full 9 by 9 grid holds 81 analyst-days and therefore 27 reports.
How do you do it in ten seconds?
Scale each dimension on its own. Three times the analysts gives three times the reports, and three times the days gives three times again, so the answer is 3 reports x 3 x 3 = 27. The general rule is output equals the rate per worker per day, times the workers, times the days, and it handles any version of the item, including the ones where the numbers do not match so neatly.
The relationship
$\text{reports} = \frac{3}{3 \times 3} \times 9 \times 9 = \frac{1}{3} \times 81 = 27$
3 / (3 x 3) reports per analyst-day, one third
9 x 9 analyst-days in the new case, 81
What it says in wordsReports equal the rate per analyst-day times the number of analyst-days.
What is a timed test like this really checking?
Wonderlic-style tests put many short items against a tight clock, so the difficulty is the time, not any single item. The format, number of items and time allowed vary by version, so confirm what the firm uses. The habit that scores on the test is the same one that keeps a model right: write the unit rate, then scale it. On a timed test, skipping an item you cannot set up in a few seconds and coming back to it is usually worth more than grinding.
Where candidates lose it
Nine is the whole trap, and it comes from answering the rhythm of the sentence rather than the arithmetic. Under a clock, strong candidates say it because it sounds finished.
The second slip is 81, which is the number of analyst-days, not reports. Say the units out loud, reports per analyst-day, and both errors disappear.
What the interviewer asks next
If 5 machines make 5 widgets in 5 minutes, how long do 100 machines take to make 100 widgets?
Two analysts together write a report in 6 days; one alone takes 10. How long does the other take alone? (15 days)
How would you pace a timed test where finishing every item is not expected?
Asked at Point72, Investment Research, New York, 2026 (Wall Street Oasis): Final round was scheduled shortly after as well as a Wonderlic/Personality test.

3 / (3 x 3)	reports per analyst-day, one third
9 x 9	analyst-days in the new case, 81

Try it first

Why does the fast answer of 9 feel right?

How do you do it in ten seconds?

What is a timed test like this really checking?

Where candidates lose it

What the interviewer asks next