Mathematics — All MCQs
1905 questions available
Q1481.Upstream speed is 60 kmph and downstream speed is 80 kmph. Find the speed of the boat in still water and speed of stream.
Correct Answer: A
Speed in still water = (80 + 60)/2 = 70 kmph. Speed of stream = (80 - 60)/2 = 10 kmph.
Q1482.A man can row downstream at 18 kmph and upstream at 10 kmph. Find speed in still water and speed of stream.
Correct Answer: D
Speed in still water = (18 + 10)/2 = 14 kmph. Speed of stream = (18 - 10)/2 = 4 kmph.
Q1483.How much is 80% of 40 greater than 4/5 of 25?
Correct Answer: D
80% of 40 = 32. 4/5 of 25 = 20. Difference = 32 - 20 = 12.
Q1484.The average of 10 numbers is 23. If each number is increased by 4, what will be the new average?
Correct Answer: B
If each number increases by 4, the average also increases by 4. New average = 23 + 4 = 27.
Q1485.Calculate the average of 22, 33, 44, 55, 66.
Correct Answer: C
Average = Sum ÷ count = (22 + 33 + 44 + 55 + 66) ÷ 5 = 220 ÷ 5 = 44.
Q1486.Divide 180 in the ratio 1: 3: 8.
Correct Answer: C
Total parts = 1 + 3 + 8 = 12. Each part = 180 ÷ 12 = 15. The parts are 15, 45, and 120.
Q1487.Sameer gets 75 marks in English, 85 marks in Computer Science and 90 marks in Mathematics out of 100 each. What is his percentage?
Correct Answer: D
Percentage = (75 + 85 + 90) ÷ 300 × 100 = 250 ÷ 300 × 100 = 83.33%.
Q1488.Evaluate using BODMAS: (2 + 4 * 3 - 5) / 3.
Correct Answer: B
First multiply: 4 * 3 = 12. Then add/subtract: 2 + 12 - 5 = 9. Finally divide: 9 ÷ 3 = 3.
Q1489.Between 15 and 100, how many multiples of 5 are there?
Correct Answer: C
The multiples are from 15 (5×3) to 100 (5×20). Number of terms = 20 - 3 + 1 = 18.
Q1490.The Least Common Multiple (LCM) of 12 and 15 is:
Correct Answer: B
Prime factors: 12 = 2^2 * 3, 15 = 3 * 5. LCM = 2^2 * 3 * 5 = 60.
Q1491.If sin α = 4/5, then cos(2α) is?
Correct Answer: A
Given sin α = 4/5. Using Pythagoras, cos α = 3/5. The double-angle identity is cos(2α) = 2cos²α - 1 = 2*(9/25) - 1 = 18/25 - 25/25 = -7/25.
Q1492.The two lines x + y = 3 and 4x + 4y = 12 intersect?
Correct Answer: C
The second equation 4x + 4y = 12 can be divided by 4 on both sides to yield x + y = 3. Since both represent the same line, they intersect at all points on the line.
Q1493.If x : y = 7 : 8 and y : z = 5 : 6, then x : z = ?
Correct Answer: A
Make y equal in both ratios: multiply x:y by 5 to get 35:40, and multiply y:z by 8 to get 40:48. Thus, x:z = 35:48.
Q1494.LCM of 30 and 36 is?
Correct Answer: B
Prime factors: 30 = 2 * 3 * 5, and 36 = 2^2 * 3^2. LCM is 2^2 * 3^2 * 5 = 4 * 9 * 5 = 180.
Q1495.What is the value of (27)^(-⅓)?
Correct Answer: C
(27)^(-1/3) is equal to 1 / (27^(1/3)) = 1 / 3.
Q1496.The decimal number 33 can be expressed in binary as?
Correct Answer: A
Converting 33 to binary by successive division by 2: 33/2 = 16 R1, 16/2 = 8 R0, 8/2 = 4 R0, 4/2 = 2 R0, 2/2 = 1 R0, 1/2 = 0 R1. Reading backwards, we get 100001.
Q1497.What is the result of 275 ÷ 100?
Correct Answer: A
Dividing any number by 100 moves the decimal place two steps to the left, which gives 2.75.
Q1498.What is 0.1 written as a fraction?
Correct Answer: A
0.1 represents one-tenth, which is written as 1/10.
Q1499.What is 1/9 of 36?
Correct Answer: B
1/9 of 36 is computed as 36 / 9 = 4.
Q1500.How can 9.4 be written as a fraction?
Correct Answer: A
9.4 = 94/10, which simplifies to 47/5 when numerator and denominator are divided by their GCD of 2.