All Free Mathematics MCQs with Answers
Every Mathematics question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
1,551 questions · page 24 of 78
- A. 70%
- B. 37%
- C. 53%
- D. 30%
Explanation: Using inclusion-exclusion, the percentage failing in at least one subject is 47% + 54% - 31% = 70%, because students failing both were…
Correct answer: 30%- A. 90% increase
- B. 45% increase
- C. 9% decrease
- D. Same as before
Explanation: Take the original salary as 100%. After a 30% increase it becomes 130%, and reducing this new salary by 30% gives 130% x 70% = 91%.
Correct answer: 9% decrease- A. 15%
- B. 65%
- C. 60%
- D. 70%
Explanation: The percentage failing in at least one subject is 40% + 45% - 25% = 60%, subtracting the 25% who failed in both because they were counted…
Correct answer: 60%- A. 38 liters
- B. 40 liters
- C. 38.5 liters
- D. 2 liters
Explanation: The 38 litres poured in represent 95% of the tank because the tank is still 5% empty.
Correct answer: 2 liters- A. 150
- B. 200
- C. 250
- D. 275
Explanation: Let the total marks be M and passing marks be P. The two statements give 0.30M = P - 50 marks and 0.45M = P + 25 marks; subtracting gives…
Correct answer: 200- A. Rs.5000
- B. Rs.25000
- C. Rs.7500
- D. Rs.8500
Explanation: Saving 20% of the salary means the original expenses are 80% of salary.
Correct answer: Rs.5000- A. 15%
- B. 12%
- C. 10%
- D. 5%
Explanation: Let the third number be 100 units. The first number is 70 units and the second is 63 units, so the second is 7 units less than the first.
Correct answer: 10%- A. 10%
- B. 15%
- C. 20%
- D. 25%
- E. None
Explanation: Keep expenditure fixed by making the consumption factor the reciprocal of the price factor.
Correct answer: 20%- A. Rs.3600
- B. Rs.4000
- C. Rs.4500
- D. Rs.3000
Explanation: After paying 10% rent, 90% of the income remains. After spending 20% of that on education, 80% remains, and after spending 25% of that on…
Correct answer: Rs.3600- A. Nothing
- B. 10%
- C. 1%
- D. 5%
Explanation: Take the previous salary as 100%. A 10% reduction makes it 90%, and a 10% increase on that reduced salary gives 90% x 110% = 99%, so the…
Correct answer: 1%- A. 456
- B. 744
- C. 912
- D. 1200
Explanation: The winner's 62% share exceeds the loser's 38% share by 24% of all votes.
Correct answer: 744- A. 1,20,000
- B. 1,10,000
- C. 1,00,000
- D. 90,000
Explanation: From 1978 to 1981 there are 3 annual increases, so the 1981 population is the 1978 population x 1.05 x 1.05 x 1.05 = population x…
Correct answer: 1,20,000- A. 70%
- B. 90%
- C. 80%
- D. 75%
Explanation: A got 90% of B, B got 125% of C, and C got 80% of D, so A = 0.90 x 1.25 x 0.80 x D = 0.90D.
Correct answer: 80%- A. 20%
- B. 18%
- C. 15%
- D. 12%
Explanation: Revenue equals tax per unit multiplied by consumption. After a 20% tax reduction and a 10% consumption increase, revenue becomes 80% x…
Correct answer: 12%- A. 3
- B. 4
- C. 5
- D. 6
Explanation: The 9 ml lotion contains 50% alcohol, so alcohol volume is 50/100 x 9 ml = 4.5 ml.
Correct answer: 6- A. 12 liters
- B. 10 liters
- C. 4 liters
- D. 2 liters
Explanation: Initially, water is 10% of 70 litres, so it is 7 litres. If x litres of water are added, (7 + x) / (70 + x) = 12.5% = 1/8, giving 56 + 8x…
Correct answer: 2 liters- A. 32%
- B. 42%
- C. 52%
- D. 62%
Explanation: Take the workforce as 100 workers: 40 are technicians and 60 are non-technicians.
Correct answer: 52%- A. 3800
- B. 4200
- C. 4400
- D. 5500
Explanation: After 5% die, 95% remain, and after 15% of that remainder leave, 85% of 95% remains: 0.95 x 0.85 = 0.8075.
Correct answer: 4400- A. Rs. 14,000
- B. Rs. 12,000
- C. Rs. 30,000
- D. Rs. 40,000
Explanation: For sales S rupees, the old commission is 5% of S = 0.05S rupees. The new remuneration is 1000 + 2.5% of (S - 4000) = 1000 + 0.025S - 100…
Correct answer: Rs. 12,000- A. Rs.500
- B. Rs.750
- C. Rs.1250
- D. Rs.1500
Explanation: A saves 5% of A's salary, while B saves 15% of B's salary. Equal savings give 0.05A = 0.15B, so A = 3B; with A + B = 2000 rupees, 4B =…
Correct answer: Rs.1500