Mathematics — All MCQs
1905 questions available
Q1461.What is the height of a triangle if its base is 8 cm and its area is 16 cm²?
Correct Answer: D
Area = (1/2) × base × height → 16 = (1/2) × 8 × height → 16 = 4 × height → Height = 4 cm.
Q1462.Two-fifths of a certain number is 60. What is the number?
Correct Answer: A
Two-fifths (2/5) of a number = 60 → number = 60 × (5/2) = 150.
Q1463.What is the value of X if X = 6 * 4 * 0 * 100 * 0.34?
Correct Answer: A
Since the expression has multiplication by 0, the entire product is 0.
Q1464.What is the product of 84 and itself?
Correct Answer: C
84 × 84 = 7056 (squaring 84).
Q1465.Simplify the expression: 3 * (4 + 3) - (4 + 5).
Correct Answer: B
3(4 + 3) – (4 + 5) = 3(7) – 9 = 21 – 9 = 12.
Q1466.If a rectangle has a length of 9 units and a width of 4 units, what is its area?
Correct Answer: B
Area of a rectangle = Length × Width = 9 × 4 = 36 square units.
Q1467.Which of these numbers is not like the others? 8, 22, 27, 7.
Correct Answer: D
7 is the only prime number in the group. The others (8, 22, 27) are composite numbers.
Q1468.If A's salary is 25% higher than B's salary, then by what percent is B's salary lower than A's?
Correct Answer: A
Let B's salary = 100. A's salary = 125. B's salary is lower by 25 from 125: (25/125) × 100 = 20%.
Q1469.The arithmetic mean of scores of a group was 52. The brightest 20% secured a mean of 80 and the dullest 25% a mean of 31. What is the mean score of the remaining 55%?
Correct Answer: C
Weighted average: (20 × 80) + (25 × 31) + (55 × x) = 100 × 52 → 1600 + 775 + 55x = 5200 → 55x = 2825 → x ≈ 51.36 (approx 51.4).
Q1470.The average weight of a group of boys is 30 kg. After a boy of weight 35 kg joins the group, the average goes up by 1 kg. Find the number of boys in the group originally.
Correct Answer: A
Let original count be n. (30n + 35) / (n + 1) = 31 → 30n + 35 = 31n + 31 → n = 4 boys.
Q1471.A boat takes half time in moving a certain distance downstream than upstream. What is the ratio of the speed of the boat in still water and that of the current?
Correct Answer: B
Time downstream is half of upstream, so speed downstream is twice upstream: b + c = 2(b - c) → b + c = 2b - 2c → b = 3c. So ratio is 3:1.
Q1472.Average weight of four boys is 24 kg. If the weight of another boy is also included, their average weight becomes 24.6 kg. Find the weight of the fifth boy.
Correct Answer: C
Total weight of 4 boys = 24 × 4 = 96 kg. Total weight of 5 boys = 24.6 × 5 = 123 kg. Fifth boy's weight = 123 - 96 = 27 kg.
Q1473.The price of sugar increases by 20%. By what percent must a housewife reduce consumption of sugar so that the expenditure is the same as before?
Correct Answer: A
Reduction % = [r / (100 + r)] × 100 = [20 / 120] × 100 = 16.66%.
Q1474.A reduction of 12.5% in the price of a dining table brought down its price to Rs. 4375. The original price of the table was:
Correct Answer: D
87.5% of original price = 4375 → original price = 4375 ÷ 0.875 = Rs. 5000.
Q1475.A and B can complete a work in 15 days and 10 days respectively. They started doing the work together but after 2 days B had to leave. How long did the whole work take to complete?
Correct Answer: C
Work in 2 days = 2 × (1/15 + 1/10) = 1/3. Remaining 2/3 done by A alone: Time = (2/3) / (1/15) = 10 days. Total time = 2 + 10 = 12 days.
Q1476.If 6 men can make 10 sofas in 2 days, then 8 men can make 8 sofas in how many days?
Correct Answer: C
Man-days for 10 sofas = 6 × 2 = 12. Man-days per sofa = 1.2. For 8 sofas: 8 × 1.2 = 9.6 man-days needed. With 8 men, days = 9.6 ÷ 8 = 1.2 days.
Q1477.The present average age of a family of five is 26 years. If the youngest is 10 years old, what was the average age of the family at the birth of the youngest member?
Correct Answer: C
Total present age = 26 × 5 = 130. 10 years ago, sum of ages of other 4 members = 130 - (5 × 10) = 80 years. Their average age then was 80 ÷ 4 = 20 years.
Q1478.Find the average of the first 20 natural numbers.
Correct Answer: D
Average of first n natural numbers = (n + 1) / 2. For n = 20: Average = 21 / 2 = 10.5.
Q1479.The average of a non-zero number and its square is 5 times the number. What is the number?
Correct Answer: A
(x + x²) / 2 = 5x → x + x² = 10x → x² - 9x = 0. Since x is non-zero, x = 9.
Q1480.5 years ago, the average age of A, B, C, and D was 45. With E joining now, the average of all five is 49. How old is E?
Correct Answer: B
Total age 5 years ago = 45 × 4 = 180. Present total age of 4 = 180 + 20 = 200. Present total of 5 = 49 × 5 = 245. Age of E = 245 - 200 = 45 years.