Free Arithmetic MCQs with Answers

6 Arithmetic MCQs from Mathematics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.

6 questions

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.

Correct answer: 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.

Correct answer: Rs. 120

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.

Correct answer: 15%

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.

Correct answer: 90

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.

Correct answer: 80 km/h

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.

Correct answer: 6 days