Aptitude & Reasoning Interview Questions and Answers
Quantitative, logical and analytical puzzles commonly used in screening rounds.
Whether you are preparing for entry-level Aptitude & Reasoning interview questions for freshers or senior software engineer interview questions addressing concurrency, scalability, and system architecture, this track provides peer-reviewed model answers with syntax walkthroughs, edge cases, and practical interview tips.
1 A train travels 300 km in 3 hours, then 200 km in 2.5 hours. What is its average speed? Easy
Average speed is total distance divided by total time, not the average of the two speeds.
Total distance = 300 + 200 = 500 km.
Total time = 3 + 2.5 = 5.5 hours.
Average speed = 500 / 5.5 ≈ 90.91 km/h.
Common trap: averaging 100 km/h and 80 km/h gives 90, which is wrong because the time spent at each speed differs.
2 A shop offers a 20% discount, then an additional 10% off the reduced price. What is the effective discount? Easy
Successive discounts multiply, they do not add.
Price 100 -> after 20% = 80. After an additional 10% on 80 -> 80 x 0.9 = 72.
Effective discount = 100 - 72 = 28%.
Formula for successive discounts a% and b%: net = a + b - (a x b)/100 = 20 + 10 - 200/100 = 28%. The naive answer 30% is wrong.
Why it matters: the second discount applies to the already reduced price, so the base is smaller and the effective saving is less than the sum of the two rates. This compounding also appears in successive percentage increases, where the multiplier for two changes is (1 + a)(1 + b) rather than 1 + a + b.
3 Find the next number: 2, 6, 12, 20, 30, ? Easy
Look at the differences: 4, 6, 8, 10, which increase by 2 each time. The next difference is 12, so the next term is 30 + 12 = 42.
Alternative view: the terms are n(n+1) for n = 1, 2, 3, 4, 5, 6 -> 2, 6, 12, 20, 30, 42.
Both patterns are valid; identifying either leads to 42. When solving number series always check first and second differences, ratios and known formulas.
Frequently Asked Questions About Aptitude & Reasoning Interviews
What do hiring managers evaluate in Aptitude & Reasoning technical rounds?
Technical interviewers look for foundational fluency, idiomatic syntax, clarity when communicating complex logic, and awareness of performance trade-offs (e.g. memory footprint, render performance, and network latency) in production environments.
What are the best interview tips for practicing Aptitude & Reasoning questions?
Use active recall: summarize each answer in your own words before revealing the model solution. Focus on explaining why a certain approach is chosen rather than just memorizing code syntax.