All Free Mathematics MCQs with Answers

1. What is 15% of 240?

• A. 30
• B. 36
• C. 42
• D. 48

Explanation: 15% of 240 = (15 ÷ 100) × 240 = 36. A faster route in the exam hall: 10% of 240 is 24 and 5% is half of that, 12, so 15% is 24 + 12 = 36.

2. If Rs. 320 is divided between two people in the ratio 3 : 5, what is the smaller share?

• A. Rs. 100
• B. Rs. 120
• C. Rs. 160
• D. Rs. 200

Explanation: The ratio has 3 + 5 = 8 parts, so one part is 320 ÷ 8 = 40. The smaller share is 3 × 40 = Rs. 120 and the larger is 5 × 40 = Rs. 200, which correctly sum to Rs. 320.

3. An item bought for Rs. 800 is sold for Rs. 920. What is the profit percentage?

• A. 12%
• B. 15%
• C. 18%
• D. 20%

Explanation: Profit = 920 − 800 = Rs. 120. Profit percentage is always calculated on cost price: (120 ÷ 800) × 100 = 15%. Calculating it on the selling price instead is the most common error in this question type.

4. The average of five numbers is 18. What is their sum?

• A. 72
• B. 80
• C. 90
• D. 95

Explanation: Average = sum ÷ count, so sum = average × count = 18 × 5 = 90. Rearranging this single relation solves nearly every averages question in aptitude papers.

5. A car covers 240 kilometres in 3 hours. What is its average speed?

• A. 60 km/h
• B. 70 km/h
• C. 80 km/h
• D. 90 km/h

Explanation: Speed = distance ÷ time = 240 ÷ 3 = 80 km/h. Note that this is average speed; the car’s instantaneous speed may have varied throughout the journey.

6. A can complete a job in 10 days and B in 15 days. Working together, how many days will they take?

• A. 5 days
• B. 6 days
• C. 8 days
• D. 12 days

Explanation: Work with rates, not days. A does 1/10 of the job per day and B does 1/15. Together they do 1/10 + 1/15 = 3/30 + 2/30 = 5/30 = 1/6 per day, so the job takes 6 days.

7. Solve for x: 3x + 7 = 22

• A. 3
• B. 5
• C. 7
• D. 9

Explanation: Subtract 7 from both sides: 3x = 15. Divide both sides by 3: x = 5. Substituting back gives 3(5) + 7 = 22, confirming the answer.