Dev10 Aptitude Test Answers

So You're Looking at the Dev10 Aptitude Test

The Dev10 Aptitude Test is an automated screening tool used by a handful of mid-tier engineering firms and tech consultancies to filter candidates before any human ever sees their resume. It's not used by Google or Microsoft. It's mostly found at smaller product companies and third-party staffing agencies that handle high-volume hiring for junior and mid-level roles. The test itself covers basic programming logic, some data structures, a few aptitude-style math questions, and occasionally a small debugging section. I've been reviewing candidates for roles that use this exact test for about four years now. We run it through our ATS and I sit in on the debriefs. The people who actually get hired from those pools are the ones who understand the pattern of the questions, not the ones who grind 50 practice sets and blank out on test day.

Where to Find Dev10 Aptitude Test Answers

There are sites that sell question banks claiming to cover the Dev10 Aptitude Test. Most of them are scraped from candidate forums and outdated PDFs. A few have updated material, but you can't tell which ones without checking the date of the last upload. I'd recommend looking for repositories that at least show community-upvoted solutions rather than just a wall of answers. The ones with voting tend to have fewer errors. One realistic issue I ran into recently involved a candidate who scored 92 percent using a popular question bank. When they came for the actual interview, I gave them a variant of one of the same questions from that bank — same concept, different numbers and a slightly different language constraint. They froze. The answer key they memorized didn't help because the test platform randomizes inputs. That's the core problem with relying on rote answer memorization for this test. It works until the question format shifts, which happens about thirty percent of the time across test cycles. The workaround I started using with my own candidates is to take whatever answers they find online and then rewrite the question parameters. If the bank says "given n=10, output the sum," I have them solve it for n=17 and n=0. If the bank gives a multiple-choice question about array rotation, I ask them to explain what happens when the array is empty. This takes about twenty minutes per topic instead of two hours of passive reading.

What the Test Actually Looks Like

The Dev10 Aptitude Test typically runs between 45 and 60 minutes. You'll see roughly two sections. The first is coding — usually three to five problems. These aren't LeetCode hard problems. Think easy to medium difficulty on a standard scale. Reversing a string, finding duplicates in an array, basic recursion, maybe a simple graph traversal if the role is backend-facing. The second section is aptitude — time-speed-distance, percentages, probability, syllogisms. Nothing that requires a calculator. Everything is designed to be solvable by hand in under two minutes per question. Here's something most people miss: the coding section uses an online compiler with limited library support. Java imports are restricted to java.util and java.io. Python users don't get access to collections beyond the standard list and dict types unless the platform explicitly states otherwise. I've seen candidates lose points because they tried to use collections.Counter in Python and got a runtime error. The test platform won't warn you about unused imports. It will just error on execution. Another counter-intuitive detail — the aptitude section sometimes includes questions that look like programming problems but are actually pure math. A candidate might see a question about binary tree levels and start writing code in their head. The fastest path is often just recognizing it as a geometric series and solving it directly. Time management matters more here than technical correctness on half the questions.

How to Actually Prepare Without Wasting Time

Don't buy a premium subscription to a question bank. Most of the free content on GitHub repos and coding forums covers the same material. The paid ones add video explanations that you'll never watch because the test is timed and you won't have bandwidth for that during the actual exam. Focus your time on three things. First, practice writing clean code under a timer. Set a fifteen-minute limit for each problem and force yourself to submit something, even if it's not perfect. The test platform doesn't penalize partial solutions. Second, drill the aptitude formulas. Speed, time, distance; percentage change; probability basics. These come up repeatedly and the patterns are nearly identical across test cycles. Third, test your own solutions on edge cases before you submit. Empty arrays, negative numbers, single-element inputs. The platform's hidden test cases almost always include at least one of these. I've seen good candidates fail this test because they optimized for the happy path. One person wrote a perfectly working merge sort but didn't handle the case where both input arrays were empty. The runtime error cost them three points and dropped their score below the cutoff. That's a ten-second fix if you think about it beforehand.

When This Test Doesn't Work

The Dev10 Aptitude Test has real limitations. It filters out people who are strong engineers but bad at timed multiple-choice math. I've hired candidates who scored in the 50th percentile on this test and went on to outperform everyone else on the team within six months. The test also disadvantages non-native English speakers on the aptitude section because the word problems are poorly phrased. Ambiguous phrasing like "the train leaves station A twice as fast as it arrives at B" shows up regularly and the intended answer depends on interpreting the author's likely intent rather than strict logic. If you're a hiring manager, I'd recommend combining this with a practical take-home assignment. The test alone tells you very little about actual coding ability. It tells you whether someone can solve easy algorithm problems quickly and do middle-school math under pressure. That's a signal, but it's a noisy one. If you're the candidate, the best approach is still the fastest: understand the patterns, practice under timed conditions, and don't obsess over memorizing answers. The test changes enough between versions that knowing how to think through a problem beats knowing that the answer to question fourteen is C.