Question 1

If 15% of a number is 45, what is the number?

Accepted Answer

Step 1: Let the number be x. Then 15% of x = 45. Step 2: (15/100) × x = 45. Step 3: x = 45 × (100/15) = 45 × (20/3) = 900/3 = 300. Therefore, the number is 300.

Question 2

A shopkeeper sells an item for ₹480, which is 20% more than the cost price. What is the cost price?

Accepted Answer

Step 1: Let the cost price be CP. Selling price = CP + 20% of CP = 1.20 × CP. Step 2: 1.20 × CP = 480. Step 3: CP = 480/1.20 = 400. Therefore, the cost price is ₹400.

Question 3

What percentage of 500 is 125?

Accepted Answer

Step 1: Use the formula: Percentage = (Part/Whole) × 100. Step 2: Percentage = (125/500) × 100 = 0.25 × 100 = 25%. Therefore, 125 is 25% of 500.

Question 4

A student scored 72 marks out of 120 in an exam. What is the percentage score?

Accepted Answer

Step 1: Use the formula: Percentage = (Obtained Marks/Total Marks) × 100. Step 2: Percentage = (72/120) × 100 = 0.60 × 100 = 60%. Therefore, the percentage score is 60%.

Question 5

If the price of an item decreases by 30%, and the new price is ₹420, what was the original price?

Accepted Answer

Step 1: Let the original price be OP. New price = OP - 30% of OP = 0.70 × OP. Step 2: 0.70 × OP = 420. Step 3: OP = 420/0.70 = 600. Therefore, the original price was ₹600.

Question 6

A shopkeeper marks an item at ₹500. He offers a discount of 12% on the marked price. What is the selling price of the item?

Accepted Answer

Step 1: Marked Price (MP) = ₹500. Step 2: Discount = 12% of 500 = (12/100) × 500 = ₹60. Step 3: Selling Price (SP) = MP − Discount = 500 − 60 = ₹440.

Question 7

In an examination, 65% of students passed. If 390 students passed, how many students appeared in total?

Accepted Answer

Step 1: Let total students = x. Step 2: 65% of x = 390. Step 3: (65/100) × x = 390. Step 4: x = 390 × (100/65) = 390 × (20/13) = 30 × 20 = 600.

Question 8

A student scored 72% in Mathematics and 68% in English. If Mathematics carries 80 marks and English carries 100 marks, what is the overall percentage score?

Accepted Answer

Step 1: Marks in Mathematics = 72% of 80 = (72/100) × 80 = 57.6 marks. Step 2: Marks in English = 68% of 100 = (68/100) × 100 = 68 marks. Step 3: Total marks obtained = 57.6 + 68 = 125.6. Step 4: Total marks = 80 + 100 = 180. Step 5: Overall percentage = (125.6/180) × 100 = 69.78% ≈ 70%.

Question 9

The price of a commodity increases by 15%. By what percentage should the consumption be reduced so that the expenditure remains the same?

Accepted Answer

Step 1: Let original price = P and consumption = C. Original expenditure = P × C. Step 2: New price = P × 1.15. Step 3: For expenditure to remain same: P × 1.15 × C' = P × C, where C' is new consumption. Step 4: C' = C/1.15 = C × (100/115) = C × (20/23). Step 5: Reduction = C − C×(20/23) = C×(3/23). Step 6: Percentage reduction = (3/23) × 100 ≈ 13.04% ≈ 13.04%. Using formula: Reduction% = (15/115) × 100 = 1500/115 ≈ 13.04%.

Question 10

A person's salary is increased from ₹24,000 to ₹27,600. What is the percentage increase in salary?

Accepted Answer

Step 1: Original salary = ₹24,000. New salary = ₹27,600. Step 2: Increase = 27,600 − 24,000 = ₹3,600. Step 3: Percentage increase = (Increase/Original) × 100 = (3,600/24,000) × 100. Step 4: Simplify: (3,600/24,000) = (36/240) = (3/20) = 0.15. Step 5: Percentage increase = 0.15 × 100 = 15%.

Question 11

A shopkeeper marks up goods by 60% above cost price. He then offers a discount of 25% on the marked price. If the cost price is ₹800, what is his profit percentage?

Accepted Answer

Step 1: Cost Price (CP) = ₹800. Step 2: Marked Price (MP) = 800 + (60% of 800) = 800 + 480 = ₹1280. Step 3: Discount = 25% of 1280 = 320. Step 4: Selling Price (SP) = 1280 - 320 = ₹960. Step 5: Profit = 960 - 800 = ₹160. Step 6: Profit % = (160/800) × 100 = 20%.

Question 12

In an election, candidate A received 45% of votes and candidate B received 35% of votes. The remaining votes were invalid. If the total number of votes cast was 8000, how many more votes did A receive than B?

Accepted Answer

Step 1: Total votes = 8000. Step 2: Votes for A = 45% of 8000 = 0.45 × 8000 = 3600. Step 3: Votes for B = 35% of 8000 = 0.35 × 8000 = 2800. Step 4: Difference = 3600 - 2800 = 800.

Question 13

A number is increased by 20%, then the result is decreased by 20%. What is the net change in the original number as a percentage?

Accepted Answer

Step 1: Let original number = 100. Step 2: After 20% increase = 100 + 20 = 120. Step 3: After 20% decrease on 120 = 120 - (20% of 120) = 120 - 24 = 96. Step 4: Net change = 96 - 100 = -4. Step 5: Net change % = (-4/100) × 100 = -4% (i.e., 4% decrease).

Question 14

A student scored 72% in English and 68% in Mathematics. If English has a weightage of 40% and Mathematics has a weightage of 60%, what is the student's overall percentage?

Accepted Answer

Step 1: Weighted score = (English score × English weightage) + (Mathematics score × Mathematics weightage). Step 2: Weighted score = (72 × 0.40) + (68 × 0.60) = 28.8 + 40.8 = 69.6%.

Question 15

The price of a commodity increases by 15% in the first year and then decreases by 10% in the second year. If the final price is ₹5175, what was the original price?

Accepted Answer

Step 1: Let original price = P. Step 2: After 15% increase: P × 1.15. Step 3: After 10% decrease: P × 1.15 × 0.90 = P × 1.035. Step 4: Final price = P × 1.035 = 5175. Step 5: P = 5175 / 1.035 = 5000.

Question 16

A person spends 30% of his income on rent, 25% on food, and 15% on transport. The remaining amount is ₹9000. What is his total monthly income?

Accepted Answer

Step 1: Total percentage spent = 30% + 25% + 15% = 70%. Step 2: Remaining percentage = 100% - 70% = 30%. Step 3: 30% of income = ₹9000. Step 4: Total income = 9000 / 0.30 = ₹30,000.

SSC GD Constable Basic Percentage

Basic Percentage— Rules & Concept

Key Points to Remember

Exam-Specific Tips

Basic Percentage — Practice Questions

60-Second Revision — Basic Percentage