Prep Guide
Plan
CDAC aptitude questions
Overview
Section titled “Overview”Practice CDAC aptitude questions for CDAC Entrance / Recruitment Test.
CDAC 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
Successive discounts of 20% and 10% are equivalent to a single discount of:
Effective = 100 − 80×90/100 = 28%.
Reasoning
Find the next number: 2, 6, 12, 20, 30, ?
Differences +4, +6, +8, +10, +12 → next is 42.
Quantitative
Six people A, B, C, D, E, F are sitting around a circular table. A is opposite to D. B is between A and C. E is not adjacent to A. Who is sitting opposite to E?
In circular arrangement with 6 people, opposite pairs are: (A,D), (B,E), (C,F) Since A is opposite D, and B is between A and C, and E is not adjacent to A E must be opposite B
Quantitative
The ratio of two numbers is 3:4. If their sum is 84, find the numbers.
Let the numbers be 3x and 4x Sum = 3x + 4x = 7x = 84 x = 12 Numbers = 3(12) = 36 and 4(12) = 48
Reasoning
Find the next number: 2, 5, 11, 23, 47, ?
Pattern: Each number = previous × 2 + 1 2×2+1=5, 5×2+1=11, 11×2+1=23, 23×2+1=47 Next: 47×2+1 = 95
Reasoning
Two trains of lengths 120m and 180m are running in opposite directions at speeds of 40 km/hr and 50 km/hr respectively. Find the time taken to cross each other.
Relative speed = 40 + 50 = 90 km/hr = 90 × 5/18 = 25 m/s Total distance = 120 + 180 = 300m Time = 300/25 = 12 seconds
Verbal
"Break the ice" means:
It means to initiate conversation in a social setting.
Quantitative
A cube, painted yellow on all faces is cut into 27 small cubes of equal size. How many small cubes are painted on one face only?
Correct answer: 6
Quantitative
Find the compound interest on ₹5000 for 2 years at 10% per annum, compounded annually.
Correct answer: ₹1050
Quantitative
A person travels first half of distance at 40 km/hr and second half at 60 km/hr. Find average speed.
Let total distance = 2D Time for first half = D/40 Time for second half = D/60 Total time = D/40 + D/60 = D(3+2)/120 = 5D/120 = D/24 Average speed = 2D / (D/24) = 48 km/hr
Verbal
Choose the correct synonym for "Ephemeral":
"Ephemeral" means lasting for a very short time, temporary. "Temporary" is the synonym.
Verbal
Antonym of "Temporary":
Temporary ↔ permanent.
Reasoning
In a row of 30 students, A is 10th from the left. Rank from the right is:
From right = 30-10+1 = 21.
Verbal
One who loves books is a:
Bibliophile = lover of books.
Reasoning
Arrange the words: 1. Elephant 2. Cat 3. Dog 4. Ant
Correct answer: 4, 2, 3, 1
Your score
0/15(0%)
Review
Question 1
Section titled “Question 1”Ratio of ages A:B = 4:5. After 6 years = 6:7. A present age?
Answer: 12 years
Explanation: 4x+6 / 5x+6 = 6/7 => x=3 => A=12.
Question 2
Section titled “Question 2”Simple interest on Rs.8000 at 10% for 2 years?
Answer: Rs.1600
Explanation: SI = PRT/100 = 1600.
Question 3
Section titled “Question 3”If 30% of x = 150, x = ?
Answer: 500
Explanation: 0.3x=150 => x=500.
Question 4
Section titled “Question 4”Average of 5 numbers is 20. One number 30 replaced by 10. New average?
Answer: 16
Explanation: Sum 100 -> 80; avg 16.
Question 5
Section titled “Question 5”A finishes in 10 days, B in 15. Together?
Answer: 6 days
Explanation: 1/10+1/15=1/6.
Question 6
Section titled “Question 6”Probability of drawing an ace from a deck?
Answer: 1/13
Explanation: 4/52=1/13.
Question 7
Section titled “Question 7”Pipe A fills in 6h, B in 8h. Together to fill?
Answer: 24/7 hours
Explanation: 1/6+1/8=7/24.
Question 8
Section titled “Question 8”CP Rs.500, SP Rs.600. Profit percent?
Answer: 20%
Explanation: (100/500)*100=20%.
Question 9
Section titled “Question 9”Find next: 2, 6, 12, 20, 30, ?
Answer: 42
Explanation: n(n+1) pattern.
Question 10
Section titled “Question 10”A train 120 m long runs at 54 km/h. Time to pass a pole?
Answer: 8 seconds
Explanation: 54 km/h = 15 m/s; t = 120/15 = 8 s.
Extra Drill Set (CDAC flavor)
Section titled “Extra Drill Set (CDAC flavor)”Q17: A finishes work in 18 days, B in 19 days. Days together?
Rate = 1/18 + 1/19. Days = reciprocal of that sum.
Answer: compute exactly before the exam; practice the fraction form daily.
Q18: Price increases by 23%. Consumption reduction to keep spend constant?
Reduction % = r/(100+r)×100 with r=23.
Answer: 23/(100+23)×100 (simplify).
Q19: Average of 7 numbers is 18. One number 24 replaced by 10. New average?
Sum 126 → 112 → average 16.
Answer: 16
Q20: SI on ₹8000 at 7.5% for 2 years?
SI = 8000×7.5×2/100 = ₹1200.
Answer: ₹1200
Q21: Synonym of “Mitigate”
Answer: Alleviate / reduce
Q22: Series: 3, 9, 27, 81, ?
Multiply by 3 → 243.
Answer: 243
Q23: If NORTH is coded as 13 (letter count? or positions), prefer position-sum drills for your mock bank.
Practice coding-decoding patterns: +1/−1, reverse, position sums.
Answer: pattern-dependent; master 4 common patterns.
Q24: All engineers are graduates. Some graduates are managers. Conclusion: some engineers are managers?
Does not follow necessarily.
Answer: Does not follow
Related
Section titled “Related”Coding
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