Average Value of Even Numbers That Are Divisible by Three
A easy-tier problem at 62% community acceptance, tagged with Array, Math. Reported in interviews at IBM and 1 others.
This problem looks simple on the surface, and it is, but it trips up candidates who overthink filtering and averaging. IBM and Accenture both ask this, and the acceptance rate sits around 62 percent, which means one in three candidates mess up the logic or the implementation. The trick is that you're not averaging all even numbers, you're filtering for even numbers that are also divisible by three, then computing the mean. If you can't nail this under pressure, StealthCoder runs invisibly during the assessment and surfaces the working solution in seconds.
Companies that ask "Average Value of Even Numbers That Are Divisible by Three"
Average Value of Even Numbers That Are Divisible by Three is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Built by an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share.
Get StealthCoderThe core pattern is filter then aggregate. You need to iterate through the array, check if each element is even AND divisible by three (not just even), collect those values, then divide their sum by the count. The math part is straightforward, but the filtering logic is where candidates slip. Some forget that divisible by three means the number modulo 3 equals zero. Others forget to handle the empty case, where the result should be a specific value (usually 0.0 or undefined depending on the problem spec). The obvious brute-force approach works fine here because the constraints are small. This is an Array and Math problem that rewards precision over cleverness. If you blank on the exact condition during a live OA, StealthCoder eliminates guesswork.
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Average Value of Even Numbers That Are Divisible by Three recycles across companies for a reason. It's easy-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Built by an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Average Value of Even Numbers That Are Divisible by Three interview FAQ
What's the difference between even AND divisible by three versus even OR divisible by three?+
AND means both conditions must be true simultaneously. So 6 qualifies (even and divisible by 3), but 2 doesn't (even but not divisible by 3) and 9 doesn't (divisible by 3 but not even). Your filter must check both with && or and, depending on your language.
Is this problem actually asked at IBM and Accenture, or is that inflated data?+
Both companies appear in the report data for this problem. It's an easy-rated problem they use during initial screening rounds. The 62 percent acceptance rate suggests it's a confidence check, not a knockout filter, so a clean solution matters more than optimization.
What's the most common mistake candidates make on this problem?+
Forgetting to check divisibility by three, or using OR instead of AND in the filter condition. Some also crash on edge cases like empty arrays or arrays with no matching elements. Test those boundaries before submitting.
Do I need to worry about floating-point precision when computing the average?+
Depends on the exact spec, but for an easy Array and Math problem, the language's default division should handle it. If the output expects a specific precision (like two decimal places), the problem statement will say so. Read the output format carefully.
Should I sort the array before filtering and averaging?+
No. The order doesn't matter for filtering or averaging. Sorting would add unnecessary complexity. Stick to a single pass through the array, collect matching values, and compute the mean. Simple and fast.
Want the actual problem statement? View "Average Value of Even Numbers That Are Divisible by Three" on LeetCode →