CMAT Quantitative Techniques 2 — Questions and Answers
Question 1: A sum doubles itself in 10 years at simple interest. What is the annual interest rate?
- 8%
- 10% (Correct answer)
- 12%
- 15%
Correct answer: 10%
SI = P when it doubles, so P = (P × R × 10)/100, giving R = 10%.
Question 2: A 20% increase followed by a 20% decrease results in what net change?
- 0%
- −2%
- −4% (Correct answer)
- −5%
Correct answer: −4%
Net factor = 1.20 × 0.80 = 0.96, representing a 4% decrease.
Question 3: If 8 workers can complete a job in 15 days, how many days will 12 workers take?
- 8
- 9
- 10 (Correct answer)
- 12
Correct answer: 10
Total work = 8 × 15 = 120 man-days; 12 workers need 120/12 = 10 days.
Question 4: A car's value depreciates by 15% each year. What is its value after 2 years if bought for $20,000?
- $14,000
- $14,450 (Correct answer)
- $14,900
- $15,200
Correct answer: $14,450
Value = 20000 × (0.85)² = 20000 × 0.7225 = $14,450.
Question 5: The average of five numbers is 40. If one number is removed, the average becomes 35. What is the removed number?
- 55
- 60 (Correct answer)
- 65
- 70
Correct answer: 60
Sum of 5 = 200; sum of 4 = 140; removed number = 200 − 140 = 60.
Question 6: A rectangle's length is increased by 20% and width decreased by 10%. What happens to its area?
- Increases by 8% (Correct answer)
- Increases by 10%
- Decreases by 8%
- Stays the same
Correct answer: Increases by 8%
New area factor = 1.20 × 0.90 = 1.08, so area increases by 8%.
CMAT Quantitative Techniques 2
A sum doubles itself in 10 years at simple interest.
What is the annual interest rate?