Bain allows a calculator on its online test (Bain's own page). So numerical questions don't fail on arithmetic. They fail on time: a careful, exact answer to question four, and no time left for six and seven.
Tonight you learn two decisions that take seconds: how long a question is allowed to take, and whether it needs a calculator at all.
The method, in 4 steps
Set the budget
Section minutes divided by questions = your seconds per question. Write it at the top of your paper. (A planning rule from our Bain guide, not Bain's.)
Options before numbers
Read the question, then the answer options, before you touch the data.
Choose the route
Options far apart: estimate and pick. Options within about 5% of each other: calculate.
Cut at 1.5×
At 1.5 times your budget, eliminate what you can, pick and submit. On TestGorilla a wrong answer costs nothing and a blank scores nothing, so never leave one blank.
Worked example
Sample item 2, free Bain guide (practice data, invented)
Example · practice contentSee the chart in our free Bain guide
| Region | Year 1 | Year 2 |
|---|---|---|
| North | 40 | 46 |
| South | 25 | 30 |
| East | 60 | 66 |
| West | 18 | 24 |
Roughly what share of Year 2 total sales came from East?
Show the workingTry it first. The method, step by step, then the answer.
- BudgetSay the section gives 12 questions in 10 minutes (one prep-site report for Bain's TestGorilla numerical): 50 seconds each, cut at 75.
- Options33, 40, 45, 50: at least 5 points apart, far more than 5% of each other. Estimate.
- Total46 + 30 + 66 + 24 = 166.
- Share66 / 166 is a hair under 66 / 165, which is exactly 0.4. So about 40%.
- Same chart, next question“Which region grew fastest?” Don't divide Year 2 by Year 1 four times. Compare change over base: North, East and West all added 6, so the smallest base wins among them (West, 6 on 18). South added 5 on 25, less than West's 6 on 18. West, with no division at all.
Answer 40%, in about twenty seconds and no calculator.
Recap · Evening 02
Pause here
- Budget first: Minutes divided by questions. Write it down before question one.
- Options before numbers: The options tell you how precise you need to be.
- Far apart, estimate. Close, calculate: Within about 5% of each other is the line.
- At 1.5×, pick and go: A guess scores sometimes. A blank never does.
Tonight · free20 min
A free percentage drill, on the clock
Percentages and shares are the core of Bain-style numerical items. Run one free drill and, before each answer, say which route you're taking: estimate or calculate.
Open it freeSources5 numbered sources, labeled by type
- DrillCase guide DrillCase: Bain online test guide: last verified 23 Sep 2026.
- DrillCase guide DrillCase: Bain SOVA numerical reasoning tips
- Official Bain & Company: Digital assessment (hiring process): platform named in your email, about 30 to 40 minutes, pen, paper and calculator allowed.
- Official TestGorilla Candidates: Common questions about assessments and tests: no going back, no penalty for a wrong answer, the timer keeps running.
- Prep site Hacking the Case Interview: Bain TestGorilla assessment (updated 15 Mar 2026): about 12 numerical questions in about 10 minutes, reported.
Independent practice. Not affiliated with Bain & Company, Sova or TestGorilla.