Untimed data study
Organize the evidence in a research journal, work with the numbers and complete a report. Review the calculations and the conclusion each question supports.
McKinsey Solve practice
Make sense of the data.
Build a team that fits.
Work through original data studies and constraint problems inspired by skills shown in Red Rock Island and Sea Wolf. Learn each workflow, check your reasoning and review the details behind your result.
Free worked examples. Sign in to check your practice access.
Focused coverage, with a clear boundary. This practice covers data analysis and constraint-based selection. It does not include Sustainable Futures Lab or legacy Ecosystem Building. Task combinations and real assessment timing can vary; use your invitation and McKinsey’s tutorials for your test.
Learn one workflow. Then put both under a clock.
Untimed constraint practice
Read site requirements, screen prospects, draft a pool and choose a final team. Check numerical ranges and required or forbidden traits together.
Timed two-module practice
Work through data analysis in 35 minutes and constraint selections in 30 minutes. These limits are our practice design. Your real invitation can specify a different duration.
All modes belong to the McKinsey Solve category. A pass for this category covers these modes for its selected period. Other assessments have separate access. Saved answers and worked reviews remain available after a pass ends.
No account needed
Two original examples. Every step explained.
Try each problem before revealing its solution. These short teaching examples are separate from the scored practice scenarios.
Example 1 · Data study
What grew, and by how much?
A restoration project counts established seedlings at two sites. Both counts use the same definition and cover all seedlings at those sites.
| Site | Before | After |
|---|---|---|
| North | 800 | 920 |
| South | 400 | 440 |
What was the percentage increase in the combined count? Round to one decimal place.
Show the calculation and report
Answer: 13.3%.
- Combine the original counts: 800 + 400 = 1,200.
- Combine the later counts: 920 + 440 = 1,360.
- Calculate the increase against the original total: (1,360 − 1,200) ÷ 1,200 × 100 = 13.333…%.
A tempting mistake: North grew by 15% and South by 10%, but averaging these percentages gives 12.5%. The original site sizes differ, so they should not have equal weight.
Report the supported conclusion: “The combined count increased by 160 seedlings, or 13.3%.” These counts alone do not establish that the restoration project caused the increase.
Journal habit: Keep each number with its site, period and unit. Recording “800” without its label makes later calculations harder to check.
Example 2 · Constraint team
Check the whole team.
Choose exactly three different organisms. Their mean power must be 6–8 and mean endurance 4–6, including the endpoints. At least one must have the Filter trait. None may have Fragile. Traits are labels, not numbers to average.
| ID | Power | Endurance | Trait |
|---|---|---|---|
| A | 7 | 5 | Filter |
| B | 8 | 4 | Stable |
| C | 6 | 6 | Neutral |
| D | 11 | 9 | Filter |
| E | 3 | 3 | Fragile |
Which three-organism team meets every requirement?
Show the team and every check
Answer: A + B + C.
- Mean power: (7 + 8 + 6) ÷ 3 = 7. Within 6–8.
- Mean endurance: (5 + 4 + 6) ÷ 3 = 5. Within 4–6.
- Required trait: A supplies Filter.
- Forbidden trait: None has Fragile.
E is ruled out by its forbidden trait. Among the remaining organisms, any three-member team containing D exceeds at least one mean limit: A+B+D exceeds power; A+C+D exceeds endurance; B+C+D exceeds both. A+B+C is therefore the only valid team here.
A useful shortcut: Convert mean ranges into team totals. For three members, power must total 18–24 and endurance 12–18. Check these totals and both trait rules before committing.
This small example teaches the checks. Our scored practice includes a screening and drafting workflow before the final team selection.
Start with McKinsey’s own introduction.
The current official overview demonstrates two tasks. In Red Rock Island, you investigate research data, organize a journal, use an integrated calculator and report conclusions. In Sea Wolf, you find prospects in a database and sort and select microbes to create treatments suited to particular sites.
That is a useful description of the skills to expect. It does not disclose a complete scoring formula or guarantee the tasks on every invitation. Our exercises use original datasets, scenarios and controls.
Watch McKinsey’s official Solve overviewUse the review to find the specific mistake.
Wrong denominator?
Distinguish percentage change from percentage points. Check units and the starting population before calculating.
Missing evidence?
Keep the source labels in your journal. Report what the data supports, and separate an observed change from a causal explanation.
A local choice broke the team?
An attractive individual can push the group mean outside a target range. Recheck the final combination against every requirement.
Ran out of time?
Compare the work you completed with what remained. Practice the unclear step untimed before trying another full sitting.
Our feedback describes your answers on these tasks. It does not reproduce McKinsey’s process score, establish an official percentile or predict selection.
McKinsey Solve practice questions
What is the McKinsey Solve assessment?
Solve is McKinsey’s digital problem-solving assessment, used in consultant recruitment. McKinsey considers the result alongside the rest of an application. Its current public introduction demonstrates Red Rock Island, which involves investigating data and reporting conclusions, and Sea Wolf, which involves selecting microbe treatments for sites. That introduction is not a guarantee that every invitation has the same tasks.
Which parts does this practice cover?
Our original data study develops research-journal organization, calculations, chart interpretation and reporting. Our original constraint practice develops screening, drafting and final team selection against numerical and trait requirements. These target skills shown in Red Rock Island and Sea Wolf. We do not simulate Sustainable Futures Lab or legacy Ecosystem Building, and this is not a complete replica of Solve.
How long is the real assessment?
Use the duration in your own invitation. McKinsey’s FAQ says that the duration is provided there, and each task has an untimed tutorial. Our timed practice has a 35-minute data module and a 30-minute constraint module. Those are editorial practice limits, not a universal official exam length. The untimed drills let you learn each module without a clock.
Does McKinsey say preparation is necessary?
No. McKinsey says no preparation is needed, and its FAQ says prior business knowledge and gaming experience are not required. Our optional practice gives you a place to work through original data and constraint problems and inspect your mistakes. We have not established that using it improves an official Solve score or hiring outcome.
Is there a pass mark or an official process score here?
We show performance on our original tasks and worked explanations. McKinsey does not publish a pass threshold or detailed scoring formula in the sources linked here. Our results do not reproduce an official product or process score, percentile, or probability of progressing. A completed practice is not evidence that you will pass the real assessment.
Can I use this during the real assessment?
No. This is for separate preparation. McKinsey’s assessment rules prohibit other websites, applications, AI tools and pre-prepared notes during Solve, and prohibit recording or capturing the assessment. Use the permitted in-assessment tools and your invitation’s instructions. Our own practice includes tools for learning; that does not grant permission to use outside tools on test day.
Which employers use Solve?
This track is for candidates invited by McKinsey. Solve is not a generic assessment vendor used interchangeably by other consulting firms. Consultant recruitment may involve Solve alongside application review and interviews, while the process for a particular role or office can differ. Follow the instructions for your own application.
What is free, and what does a pass include?
The two worked examples on this page are free without an account. Sign in to check your practice access before starting a drill or timed sitting; a pass may be required before the first attempt. A McKinsey Solve pass covers the data and constraint modes in this category only, for the selected period. It does not unlock other assessments. Saved answers and explanations remain free to review.
For the evidence behind current task descriptions and the limits of candidate reports, read our McKinsey Solve format guide.
Choose the skill you want to work on.
Start with a data study, focus on constraint selections, or combine both in timed practice.
Check practice accessSources checked September 11, 2026. Game Assessment Prep is independent and is not affiliated with or endorsed by McKinsey & Company. Red Rock Island, Sea Wolf and Solve are referenced to explain the relevant assessment; our content and scoring are original. No actual assessment questions or proprietary interface assets are reproduced.