Cognizant Aptitude Screening 3 — Questions and Answers
Question 1: The average of 5 consecutive even numbers is 26. What is the largest number?
- 28
- 30 (Correct answer)
- 32
- 34
Correct answer: 30
The middle number is 26; the five numbers are 22, 24, 26, 28, 30, so the largest is 30.
Question 2: P is 25% more efficient than Q. If Q alone can complete a job in 20 days, how many days does P alone take?
- 15 days
- 16 days (Correct answer)
- 18 days
- 25 days
Correct answer: 16 days
P's rate = 1.25 × (1/20) = 1/16, so P takes 16 days.
Question 3: Two numbers are in the ratio 3:5. If each is increased by 10, the ratio becomes 5:7. What are the numbers?
- 15 and 25 (Correct answer)
- 10 and 20
- 12 and 20
- 20 and 30
Correct answer: 15 and 25
(3x+10)/(5x+10) = 5/7 → 21x+70 = 25x+50 → x=5; numbers are 15 and 25.
Question 4: Find the probability of drawing a red king from a standard deck of 52 cards.
- 1/26 (Correct answer)
- 1/13
- 2/13
- 1/52
Correct answer: 1/26
There are 2 red kings in 52 cards; probability = 2/52 = 1/26.
Question 5: If the compound interest on ₹8000 at 10% per annum for 2 years is ₹X, find X.
- ₹1600
- ₹1680 (Correct answer)
- ₹1760
- ₹1800
Correct answer: ₹1680
A = 8000×(1.1)² = 8000×1.21 = 9680; CI = 9680−8000 = 1680.
Question 6: A boat travels 30 km upstream in 6 hours and 30 km downstream in 3 hours. What is the speed of the current?
- 2.5 km/h (Correct answer)
- 5 km/h
- 7.5 km/h
- 10 km/h
Correct answer: 2.5 km/h
Upstream speed = 5 km/h, downstream = 10 km/h; current = (10−5)/2 = 2.5 km/h.
Question 7: How many prime numbers exist between 50 and 70?
- 3
- 4 (Correct answer)
- 5
- 6
Correct answer: 4
Primes between 50 and 70 are 53, 59, 61, 67 — exactly 4 primes.
Cognizant Aptitude Screening 3
The average of 5 consecutive even numbers is 26.
What is the largest number?