Percentage Questions

Multiple choice
  1. I alone is sufficient and II alone is not sufficient to answer the question.

  2. II alone is sufficient and I alone is not sufficient to answer the question.

  3. Both I and II together are sufficient, but neither statement alone is sufficient to answer the question.

  4. Both I and II together are not sufficient to answer the question and additional data specific to the question is needed.

  5. None of these

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let CP = 100, SP = 125. MP = x. Statement I: 0.96x = 125, so x is known. Statement II: CP = 0.8 * SP, which is 100 = 0.8 * 125, which is always true and provides no info on MP. Statement I is sufficient.

Multiple choice
  1. 5

  2. 4.04

  3. 4

  4. 3.96

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The net annual increase is 2.5% - 0.5% = 2%. However, percentage increase compounds annually. After 2 years, the factor is (1.02)^2 = 1.0404, giving a 4.04% total increase. Option A (5%) incorrectly adds the rates, while C (4%) uses simple interest instead of compound.

Multiple choice
  1. 23

  2. 34

  3. 50

  4. 12

  5. None of these

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Original area = L × B. New length = 1.3L (30% increase), new breadth = 1.2B (20% increase). New area = 1.3L × 1.2B = 1.56LB. Percentage change = (1.56 - 1) × 100 = 56% increase. None of the given options (23, 34, 50, 12) equal 56%, so 'None of these' (E) is correct. The correct answer should be 56% increase.

Multiple choice
  1. 31.25%

  2. 33.25%

  3. 32.50%

  4. 50.00%

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let initial income be 100. Initial expenditure = 75, savings = 25. New income = 120 (20% increase). New expenditure = 82.5 (10% increase on 75). New savings = 120 - 82.5 = 37.5. Percentage increase in savings = (37.5 - 25)/25 × 100 = 50%.

Multiple choice
  1. 8%

  2. 10%

  3. 20%

  4. 15%

  5. 5%

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let original price = 100, consumption = 100 units. New price = 120. New expenditure = 108. New consumption = 108/120 = 0.9 of original. Percentage decrease = (1 - 0.9) x 100 = 10%. The consumption must decrease by 10% to keep expenditure increase at only 8%.

Multiple choice
  1. 300%

  2. 400%

  3. 1600%

  4. 1500%

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Area of a circle = pi r^2. When radius increases 4 times, new area = pi(4r)^2 = 16 pi r^2. The area increases by 16 times, which is a 1500% increase (calculated as (16-1) x 100%). 300% would mean 4 times area, 400% would mean 5 times, and 1600% would mean 17 times the original area. Only 1500% correctly represents a 16-fold increase.

Multiple choice
  1. 4000

  2. 4500

  3. 5000

  4. 5100

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Work backwards from present to past by reversing the compound growth. If population grew 10% each year for 2 years to reach 6171, divide by 1.10 twice: 6171 ÷ 1.21 = 5100. Answer D is correct.

Multiple choice
  1. 25%

  2. 30%

  3. 35%

  4. 20%

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Marked price = Rs 600. After first discount of 15%: 600 × 0.85 = 510. After second discount of 20%: 510 × 0.80 = 408 (CP). Add transport: 408 + 28 = 436 (total cost). SP = 545. Gain = 545 - 436 = 109. Gain% = (109/436) × 100 = 25%.

Multiple choice
  1. 76.5%

  2. 80%

  3. 80.4%

  4. 81%

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

After 10% leave: 90% remain. From this remaining 90%, another 15% leave: 15% of 90% = 13.5%. Total remaining = 90% - 13.5% = 76.5%. Option B (80%) incorrectly adds the percentages (10% + 15% = 25%, so 100-25=75) or treats them independently.