Preparation guide
Zerodha Aptitude Questions
Overview
This page has Zerodha aptitude questions with full solutions - numerical ability, verbal, and logical reasoning - in the style students report for the Zerodha Assignment / Interviews. Start with the timed mock quiz, then work the solved set and log every miss by topic.
Zerodha Aptitude Mock Quiz
Timed placement-style MCQs with score and explanations after you submit. Use it to check speed and accuracy before the real test.
Questions15
Time10 min
Quantitative
If Thursday was the day after the day before yesterday five days ago, what is the least number of days ago when Sunday was three days before the day after tomorrow?
Correct answer: Requires careful day calculation (typically 2-4 days ago)
Quantitative
If the sum of the first 50 natural numbers is S, what is the value of S?
Sum of first n natural numbers = n(n + 1)/2 For n = 50: S = 50 × 51 / 2 = 1275
Reasoning
Series: 1, 4, 9, 16, 25, ?
Perfect squares → 36.
Verbal
Problem: Choose the correct sentence: a) She likes reading, writing, and to dance b) She likes reading, writing, and dancing c) She likes to read, writing, and dancing
Parallel structure requires same form: all gerunds or all infinitives. Option b maintains parallelism with all gerunds.
Quantitative
The average of 6 numbers is 25. If one number is 30, what is the average of the remaining 5 numbers?
Correct answer: 24
Reasoning
If in a certain code, FLOOR is written as EKNQQ, how is TABLE written?
Each letter −1: T→S, A→Z, B→A, L→K, E→D → SZAKD.
Verbal
Choose the correct form: "Neither the teacher nor the students _____ present."
Correct answer: were
Quantitative
A mixture contains milk and water in the ratio 5:3. If 10 liters of water is added, the ratio becomes 5:4. Find the quantity of milk in the mixture.
Let milk = 5x, water = 3x After adding 10 liters water: Milk = 5x, Water = 3x + 10 Ratio: 5x/(3x + 10) = 5/4 20x = 5(3x + 10) 20x = 15x + 50 5x = 50 x = 10 Quantity of milk = 5x = 5 × 10 = 50 liters
Reasoning
All cats are dogs. Some dogs are rats. Conclusions: I. Some cats are rats. II. Some rats are dogs.
II follows from "some dogs are rats". I does not necessarily follow.
Reasoning
How many 9s are there between 1 and 100?
9,19,29,39,49,59,69,79,89,90-99 → 20 nines.
Verbal
A bouquet of flowers _____ on the table.
Bouquet is singular.
Quantitative
If "CAT" is coded as "3120", "DOG" is coded as "4157", then how is "RAT" coded?
Pattern analysis: - C = 3, A = 1, T = 20 → "3120" - D = 4, O = 15, G = 7 → "4157" Pattern: Position of letter in alphabet For "RAT": - R = 18 - A = 1 - T = 20
Quantitative
A is twice as efficient as B. Together they complete a work in 12 days. In how many days will A alone complete it?
Let B's efficiency = 1 unit/day A's efficiency = 2 units/day Together: 1 + 2 = 3 units/day Total work = 3 × 12 = 36 units A alone: 36 / 2 = 18 days
Reasoning
If P means +, Q means −, R means ×, then 18 R 2 P 6 Q 4 = ?
18 × 2 + 6 − 4 = 36 + 6 − 4 = 38.
Verbal
There are two pipes in a tank. Pipe A is for filling the tank and pipe B is for emptying the tank. If A can fill the tank in 10 hours and B can empty the tank in 15 hours then find how many hours will it take to completely fill a half empty tank?
Correct answer: 15 hours
Your score
0/15(0%)
Review
Zerodha aptitude topics students usually practice
- Numerical / quantitative: percentages, profit and loss, ratios, time and work, averages, SI/CI, speed-distance
- Logical reasoning: series, coding-decoding, blood relations, seating, syllogisms
- Verbal ability: grammar, vocabulary, error spotting, idioms
Numerical ability questions
Q1: Algebra ages
Problem: Father is 3 times as old as son. After 12 years he will be twice as old. Son’s present age?
Solution: 3x + 12 = 2(x + 12) → 3x + 12 = 2x + 24 → x = 12.
Answer: 12 years
Q2: Average speed
Problem: A person covers a distance at 60 km/h and returns at 40 km/h. What is the average speed for the whole trip?
Solution: For equal distances, average speed = 2ab/(a+b). = 2×60×40 / (60+40) = 4800/100 = 48 km/h.
Do not take the arithmetic mean (50); that would be wrong here.
Answer: 48 km/h
Q3: Boat upstream
Problem: A boat’s speed in still water is 15 km/h and the stream is 3 km/h. How long to cover 36 km upstream?
Solution: Upstream speed = 15 − 3 = 12 km/h. Time = 36 / 12 = 3 hours.
Answer: 3 hours
Q4: Percentage of percentage
Problem: What is 15% of 20% of 400?
Solution: 20% of 400 = 80. 15% of 80 = 12.
Answer: 12
Q5: A and B together
Problem: A can finish a job in 10 days and B in 20 days. How long will they take working together?
Solution: A’s one-day work = 1/10. B’s one-day work = 1/20. Together = 1/10 + 1/20 = 3/20 per day. Time = 20/3 ≈ 6.67 days (6 days 16 hours).
Answer: 20/3 days
Q6: Compound ratio
Problem: If two ratios are 3:5 and 5:7, what is the compound ratio?
Solution: Compound ratio = (3/5) × (5/7) = 3/7, written as 3:7.
Answer: 3:7
Q7: CI half yearly
Problem: CI on ₹8000 at 10% p.a. for 1 year compounded half-yearly?
Solution: Rate per half-year = 5%. Amount = 8000 × (1.05)² = 8000 × 1.1025 = 8820. CI = 820.
Answer: ₹820
Q8: Train and pole
Problem: A train 150 meters long passes a pole in 15 seconds. What is its speed in km/h?
Solution: Distance = 150 m = 0.15 km. Time = 15 s = 15/3600 h = 1/240 h. Speed = 0.15 ÷ (1/240) = 0.15 × 240 = 36 km/h.
Faster check: 150/15 = 10 m/s → 10 × 18/5 = 36 km/h.
Answer: 36 km/h
Q9: Worker scaling
Problem: Eight workers finish a job in 10 days. How many days will 10 workers take for the same job (same pace)?
Solution: Total man-days = 8 × 10 = 80. Days for 10 workers = 80 / 10 = 8 days.
Answer: 8 days
Q10: Discount successive
Problem: Two successive discounts of 10% and 20% equal a single discount of?
Solution: Net multiplier = 0.9 × 0.8 = 0.72 → 28% single discount.
Answer: 28%
Verbal ability questions
Q11: Idiom - piece of cake
Problem: What does ‘a piece of cake’ mean?
Solution: It means something very easy.
Answer: Very easy
Q12: Error spotting
Problem: Spot the error: ‘Neither of the boys have submitted their assignment.’
Solution: ‘Neither’ is singular, so the verb should be ‘has’ (and ideally ‘his’ / ‘their’ per style guide). Correct: Neither of the boys has submitted his assignment.
Answer: have → has
Q13: Antonym - verbose
Problem: Best antonym of ‘verbose’?
Solution: Verbose = wordy. Opposite: concise.
Answer: Concise
Q14: Error spotting tense
Problem: Identify the error: He go to school yesterday.
Solution: Past time marker needs past tense: went.
Answer: go → went
Q15: Synonym - candid
Problem: Choose the best synonym of ‘candid’.
Solution: ‘Candid’ means frank or straightforward. Closest: frank.
Answer: Frank
Q16: Synonym - mitigate
Problem: Choose the best synonym of ‘mitigate’.
Solution: ‘Mitigate’ means to make less severe. Closest match: alleviate.
Answer: Alleviate
Reasoning ability questions
Q17: Direction return
Problem: You walk 2 km east, 3 km south, 2 km west. How far from start?
Solution: East/west cancel; 3 km south from start.
Answer: 3 km south
Q18: Number series gap
Problem: Find the missing number: 5, 11, 23, 47, ?
Solution: ×2+1 pattern: 5→11→23→47→95.
Answer: 95
Q19: Series multiply
Problem: Find the next number: 3, 9, 27, 81, ?
Solution: Each term is multiplied by 3. Next = 81 × 3 = 243.
Answer: 243
Q20: Blood relation
Problem: Pointing to a photograph, Ravi says, ‘She is the daughter of my mother’s only son.’ How is the girl related to Ravi?
Solution: Ravi’s mother’s only son is Ravi himself (assuming one son). The girl is therefore Ravi’s daughter.
Answer: Daughter
Q21: Series alternate
Problem: Find next: 2, 3, 5, 8, 12, ?
Solution: Differences +1,+2,+3,+4,+5 → next diff 5 → 17.
Answer: 17
Q22: Venn conclusion
Problem: Some doctors are teachers. All teachers are writers. Conclusion: Some doctors are writers?
Solution: Some doctors who are teachers must be writers. Follows.
Answer: Follows
Timed practice tips for Zerodha
- First pass: only high-confidence questions
- Mark and skip time sinks early
- Keep verbal accuracy high - these are easy marks if you stay calm
- Run the mock quiz at least three times a week under real timing
- Sleep properly the night before; fatigue hurts DI and calculation accuracy