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WBCS Preliminary Question – 2021
157. A vehicle covers half the distance with uniform speed v1 and the other half with uniform speed v2. The average speed of the vehicle is
177. Manoj can type 100 pages of a report in 10 hours and Bobby can do the same in 15 hours. They worked together for 5 hours. The remaining work was completed by Lucy in 2 hrs. If they received Rs. 2,400 for whole work, Lucy got
(A) Rs. 300
(B) Rs.250
(C) Rs. 200
(D) Rs. 400
178. The ratio of 6 inch to 4 feet will be
(A) 1 : 6
(B) 1 : 4
(C) 3 : 2
(D) 1 : 8
181. A ladder is kept against a wall. The top of the ladder touches the wall at a height of 270 cm from the ground. The base of the ladder is 54 cm away from the wall on the ground. Find the length of the ladder.
182. 480 students out of 1500 are enrolled in NCC. What percentage of students are not there in NCC ?
(A) 70%
(B) 68%
(C) 73%
(D) 64%
183. A building which is 64 feet high cast a shadow of length 96 feet. The height of telephone tower, which cast a shadow of length 180 feet, under similar condition is
(A) 80 feet
(B) 100 feet
(C) 120 feet
(D) 90 feet
188. Mohan takes 6 hours to do a job. Laltu takes 10 hours to do the same job. How long should it take if Mohan and Laltu work together the same job ?
192. A train is 150 m long. It is running at a speed of 41 kmph. A man is running at 11 kmph in the same direction as the train. In what time will it pass the man ?
1. Numbers are placed in the figure below on the basis of some rules. Find the correct alternative to replace the question mark.
(A) 35
(B) 37
(C) 39
(D) 41
2. A caterpillar crawls up a pole 75 Inches high, starting from the ground. Each day it crawls up 5 Inches and each night it slides down 4 Inches. When will it first reach the top of the pole ?
(A) The 70th day
(B) The 71st day
(C) The 72nd day
(D) The 75th day
3. The smallest composite number is
(A) 1
(B) 2
(C) 4
(D) 3
4. Let x1, x2, _____, x100 be 100 numbers such that xi+ xi+1 = 100 for all i. If x10= 1, then the value of x1is
(A) 100
(B) 99
(C) 101
(D) 1
5. 2162/3 ÷ (p2/9)-3/2 = 2x 3y pz the values of x,y, z are
(A) x = 2, y = -1, z = 3
(B) x = -1, y = 2, z = 3
(C) x = 3, y = -1, z = 2
(D) x = 2, y = 3, z = -1
6. What number should come next in the sequence 6, 11, 21, 36, 56 ____ ?
(A) 78
(B) 81
(C) 82
(D) 86
7. In writing the numbers from 10 to 100, how many times is the digit 7 used ?
(A) 20
(B) 19
(C) 10
(D) 11
8. Choose the two correct numbers in the marked places of the multiplication below
(A) 8, 4
(B) 6, 8
(C) 4, 8
(D) 8, 6
9. Find the odd one out.
(A) 27
(B) 64
(C) 81
(D) 125
10. The speed of an ant is 75 cm/sec. The ant travels a day is
(A) 64800 m/day
(B) 648000 m/day
(C) 648000 cm/day
(D) 64800000 cm/day
11. The sum of all the internal angles of a hexagon is ?
(A) 7200
(B) 3600
(C) 1800
(D) 6000
12. What comes next In the sequence 1, 3, 7, 15, 31, 63, ____ ?
(A) 127
(B) 125
(C) 121
(D) 129
13. What number should come next In the sequence 6, 18, 72, 360, 2160, ____ ?
1. What is the ratio of the perimeter of the shaded region to the circumference of the circle?
(A) 3/4
(B) 4+π/4π
(C) 2π/4+π
(D) 4+π/2π
2. If per cent increase in radius of cylinder is 300. Then volume of the cylinder changes by how much percent? (Keeping height of the cylinder constant)
(A) 1500%
(B) 600%
(C) – 600%
(D) None of the above
3. The difference of the ages of Rohit and Axar is 12 years. The ratio of their ages is 3 : 5 . The age Axar is
(A) 32 years
(B) 24 years
(C) 28 years
(D) 30 years
4. Two pipes can fill a cistern in 20 minutes and 30 minutes respectively. Both pipes being opened, time when the first pipe must be turned off so that the cistern may be filled in 10 minutes more will be
(A) 8 minutes
(B) 9 minutes
(C) 10 minutes
(D) 12 minutes
5. A clock strikes one at 1 o’ clock, twice at 2 o’clock, ….. twelve times at 12 o’ clock. How many times will the bell strike in course of 2 days ?
(A) 78
(B) 264
(C) 312
(D) 444
6. P is greater than Q by 60% and greater than R by 30%. The ratio of Q and R is
(a) 1 : 2
(b) 2 : 1
(c) 13 : 16
(d) 16 : 13
7. A dishonest dealer defrauds his seller and buyer by using forged weights to the extent of 20%. His true gain per cent is
(a) 20%
(b) 40%
(c) 44%
(d) 50%
8. In a mixture ratio of first and second liquid is 2 : 3 and in another mixture ratio of those two liquids is 5 : 4. Ratio in which the two mixture be mixed so that quantity of two liquids in the new mixture of two liquid in the new mixture be equal is
(a) 2 : 5
(b) 3 : 7
(c) 5 : 9
(d) 9 : 11
9. What should come in the place of question mark in the following series?
1. If a * b = ab + b – a, what is the value of c such that c* (2*5) = 97 ?
(A) 8
(B) 7
(C) 3
(D) 91
2. Due to rotten fish, a fish trader forces to sell in 10% loss. If the purchase value is Rs. 250, the selling price will be
(A) Rs. 225
(B) Rs. 240
(C) Rs. 235
(D) Rs. 230
3. A man won Rs. 60,000 in a lottery. 35% of the money was taken by the Govt. as a tax. He actually receives
(A) Rs. 21,000
(B) Rs. 39,000
(C) Rs. 18,000
(D) Rs. 40,000
4. Due to some error in the weighting machine, Aahana’s weight was shown 72 kg as against the actual value of 80 kg. The percentage error is
(A) 9%
(B) 8%
(C) 10%
(D) None of the above
5. 40% of A is 60% of B. A : B will be
(A) 2 : 3
(B) 3 : 2
(C) 7 : 8
(D) 8 : 7
6. Ratio of Bus and Train fare is 4 : 5. If Bus fare increases by 10% and Train fare increases by 20%, new ratio of Bus and Train fare will be
(A) 15 : 11
(B) 7 : 13
(C) 11 : 15
(D) 5 : 9
7. In an examination, 35% students fail in Mathematics, 15% fail in English. If 10% fail in both, the pass percent is
(A) 60%
(B) 40%
(C) 35%
(D) 25%
8. A person, standing on a railway platform 120 meters long, notices that a train, which passed him in 5 seconds, passed completely through the station in 15 seconds. The length of the train is
(A) 50 m
(B) 60 m
(C) 100 m
(D) 55 m
9. A man deposited Rs. 3,000 in a Bank and Rs. 2,500 in a Post Office. Rate of interest of Bank is 1/2% more than that of Post Office. If he gets Rs. 235 as total interest at the end of the year, the rate of interest of Post Office is
(A) 2%
(B) 21/2%
(C) 4%
(D) 41/2%
10. The population of a district increases by 4% during the first year and decreases by 5% during the second year. If the present population of a district is 494000, two years ago it was
(A) 475000
(B) 500000
(C) 525000
(D) 600000
11. A box contains one red ball, one blue ball and one green ball. The ratio of the weight of the red and blue ball is 5 : 6 and that of blue and green ball is 5 : 4. If the blue ball weights 60g, the weight of the green ball is
1. The greatest number consisting of five digits which is a perfect square is —
(A) 99866
(B) 99856
(C) 99846
(D) 99876
2. The ratio of the radius of two circles is 5 : 4. What is the ratio of their areas ?
(A) 5 : 4
(B) 25 : 16
(C) 6 : 7
(D) 9 : 13
3. A profit of 25% is made by selling an article for Rs. 30. If the article was sold for Rs. 33.60, the profit would have been
(A) 30%
(B) 35%
(C) 40%
(D) 45%
4. The incomes of A and B are in the ratio 3 : 2 and their expenditures are in the ratio 5 : 3. If each saves Rs. 1,000, then B’s income is-
(A) Rs. 3,000
(B) Rs. 4,000
(C) Rs. 6,000
(D) Rs. 800
5. There are 100 questions in a question paper, each carrying 2 marks. But there is a negative marking. 1 mark is deducted for each question answered incorrectly. A student answering all the questions got 80 marks. The number of questions correctly answered by him is –
(A) 70
(B) 60
(C) 80
(D) 75
6. What is the least number to be added to 1500 to make it a perfect square ?
(A) 12
(B) 15
(C) 21
(D) 25
7. If 17200 is divided by 18, the remainder is —
(A) 16
(B) 17
(C) 5
(D) 1
8. The next term in the sequence 4, 10, 22, 46, … is –
(A) 66
(B) 76
(C) 56
(D) 94
9. The speeds of three cars are in the ratio 2 : 3 : 4. The ratio between the time taken by these cars to travel the same distance is –
(A) 2 : 3 : 4
(B) 4 : 3 : 6
(C) 3 : 4 : 6
(D) 6 : 4 : 3
10. A sum of money kept in a bank amounts to Rs. 1,240 in 4 years and Rs. 1,600 in 10 years at simple interest. Find the sum.
(A) Rs.1,000
(B) Rs.800
(C) Rs.1,950
(D) Rs.1,100
11. If 3 mangoes are sold for the cost price of Rs. 4, the profit is—
(A) 16 1/3 %
(B) 33 1/4 %
(C) 33 1/3 %
(D) 40 1/2 %
12. What is the digit in the unit place of (232)33 ?
(A) 6
(B) 4
(C) 2
(D) 8
13. How many ways a captain and a vice-captain can be selected from a team of 11 players ?
(A) 99
(B) 110
(C) 98
(D) 22
14. A clock strikes once at 1 o’ clock, twice at 2 o’ clock, ……… twelve times at 12 o’ clock. How many times will the bell strike in course of 2 days ?
(A) 78
(B) 264
(C) 312
(D) 144
15. A number X lies between 0 and 1. which of the following is true ?
(A) X > √x
(B) X > 1/x
(C) X3 > X2
(D) 1/x > √x
16. The salary of Anup is 30% more than of Barun. Find what percentage is the salary of Barun less than that of Anup ?
1. In a class of 60 where boys are twice that of girls, Ram ranked 17th from the top. If there are 9 boys ahead of Ram, how many girls are after him in the rank ?
(A) 26
(B) 13
(C) 12
(D) 33
2. Flight to Mumbai leaves every 5 hours. At the information counter I learnt that the flight took off 25 minutes before. If the time now is 10.45 a.m., what is the time for the next flight ?
(A) 2.20 a.m.
(B) 3.30 a.m.
(C) 3.55 P.m.
(D) 3.20 P.m.
3. What should come in the place of question mark in the following series ?
3, 8, 6, 14, ?, 20
(A) 11
(B) 10
(C) 8
(D) 9
4. Babloo ranked 16th from the top and 29th from the bottom among those who passed an examination. 6 boys did not participate in the competition and 5 failed in the examination. How many boys were there in that class ?
3. Simantika sold two radios for Rs. 2000 each. On one she gains 16 % and on the other she losses 16 %. Find her gain or loss per cent in the whole transaction.
(A) 5.28
(B) 2.56
(C) 4.68
(D) 8.01
4. The difference between 78% of a number and 59% of the number is 323. What is 62% of that number ?
(A) 1054
(B) 1178
(C) 1159
(D) 1037
5. The population of a city increases at the rate of 15% pa. If its population was 4000 at the end of 2009. Find its population at the end of 2011 .
(A) 5390
(B) 4780
(C) 5290
(D) 8256
6. How many iron rods each of length 14 m. and diameter 4 cm. can be made out of 0.88 m3 of iron ?
(A) 45
(B) 50
(C) 65
(D) 80
7. 879 x 439 + 879 x 321 = ?
(A) 668040
(B) 669040
(C) 667030
(D) 666040
8. 48% of the first number is 60% of the second number. What is the ratio of the first number to the second number ?
(A) 4 : 7
(B) 3 : 4
(C) 5 : 4
(D) 3 : 2
9. The product of two consecutive odd numbers is 6723. What is the greater number ?
(A) 89
(B) 85
(C) 91
(D) 83
10. 60 : 15 :: * : 1/4 , Find *
(A) 1.1
(B) 2.1
(C) 1
(D) 0.1
11. What is the value of two-fifth of 60% of 320 ?
(A) 76.6
(B) 38.4
(C) 76.8
(D) 37.4
12. The difference of the age of Riju and Rivu is 12 years. The ratio of their ages is 3 : 5. The age of Rivu is
(A) 32 years
(B) 24 years
(C) 28 years
(D) 30 years
13. Average of 5 numbers is 50. If every number is multiplied by 2, find the average.
(A) 52
(B) 48
(C) 100
(D) 25
14. A boat is rowed downstream at 35 Km./hr. and upstream at 17 km./hr. Find the speed of the stream.
(A) 4 km./hr.
(B) 9 km./hr.
(C) 6 km./hr.
(D) 7 km./hr.
15. Find the missing number from the series.
8, 15, 28, 53, ?, 199
(A) 104
(B) 103
(C) 102
(D) 101
16. If the difference of the square of two natural numbers is 19, find the sum of the squares of these numbers.
(A) 220
(B) 169
(C) 189
(D) 181
17. A circular wire of radius 42 cm. is cut and bent in the form of an rectangle whose sides are in the ratio of 6 : 5. Find the smaller side of the rectangle.
(A) 60 cm.
(B) 120 cm.
(C) 177 cm.
(D) 110 cm.
18. Triangle ABC is right-angled at B. If AB = 24 mm. and BC = 7 mm. then AC = ?
(A) 31 mm
(B) 21 mm
(C) 35 mm
(D) 25 mm
19. Every angle of a regular hexagon is
(A) 90°
(B) 120°
(C) 135°
(D) 145°
20. Find the value of K for which the lines
5x + 3y + 2 = 0 and 3x – Ky + 6 = 0 are perpendicular.
3. The least integer multiplied by 112 to make the result a perfect square is —
(A) 2
(B) 7
(C) 3
(D) 11
4. A square lamina is made from three square laminae, whose sides are 2 cm, 3 cm, and 6 cm. The side of the new square lamina is —
(A) 11 cm
(B) 10 cm
(C) 7 cm
(D) 9 cm
5. Two numbers are in the ratio 7 : 9 and their difference is 6. The numbers are —
(A) 49, 55
(B) 91, 97
(C) 21, 27
(D) 42, 54
6. Find the missing term of the series :
24, 25, 27, ?, 39, 55
(A) 29
(B) 31
(C) 33
(D) 35
7. A man sells an article at a loss of 10%. If he had sold it for Rs. 40 more he would have gained 10%. The cost price of the article is —
(A) Rs. 250
(B) Rs. 200
(C) Rs. 300
(D) Rs. 180
8. At every forty five minutes a train crosses the Maharaja Gate. Just 10 minutes ago one train crossed the gate and next will be crossing at 9.35 A. M. What is time now ?
(A) 9.15 A.M.
(B) 9.00 A.M.
(C) 9.05 A.M.
(D) 9.10 A.M.
9. The difference between two numbers is 15 and the difference between their square root is 1. The smaller number is —
(A) 81
(B) 49
(C) 36
(D) 25
10. 12 : 20 = * : 25, the missing term is —
(A) 16
(B) 24
(C) 18
(D) 15
11 . Manish can type 500 words in 10 minutes and Rana can type 400 words in 10 minutes. In how many minutes they can together type 3600 words ?
(A) 60 minutes
(B) 45 minutes
(C) 40 minutes
(D) 38 minutes
12. Find out the missing figure :
46, 56, 67, 80, ?, 104
(A) 101
(B) 88
(C) 83
(D) 91
13. A cube painted black on all sides. It is then cut into 64 cubes of equal size. How many of these smaller cubes are painted on one side only ?
(A) 4
(B) 8
(C) 16
(D) 24
14. The area of a sphere in sq.cm. is 3 times its volume in cu.cm. The diameter of the sphere is :
1. The ratio of the radii of two circle is 5 : 4. What is the ratio of their areas ?
(A) 5 : 4
(B) 25 : 16
(C) 6 : 7
(D) 9 : 13
2. A profit of 25% is made by selling an article for Rs.30. If the article was sold for Rs.33.60, the profit would have been
(A) 30%
(B) 35%
(C) 40%
(D) 45%
3. Three times the first of three consecutive odd integers is 3 more than twice the third. What is the third integer ?
(A) 9
(B) 15
(C) 13
(D) 11
4. If a four digit number a381 is divisible by 11, what is the value of a ?
(A) 5
(B) 6
(C) 7
(D) 8
5. A sum of money is kept in a bank account to Rs.1240 in 4 years and Rs.1600 in 10 years at simple interest. Find the sum :
(A) Rs.1000
(B) Rs.800
(C) Rs.1050
(D) Rs.1100
6. A clock strikes once at 1 O’clock , twice at 2 O’clock ,….., twelve times at 12 O’clock . How many times will the bell be struck in course of 2 days ?
(A) 78
(B) 264
(C) 312
(D) 144
7. The salary of Anup is 30% more than that of Buran. Find by what percentage is the salary of Barun less than that of Anup
(A) 26.12%
(B) 21.23%
(C) 23.07%
(D) 27.03%
8. A captain and a vice-captain are to be chosen out of a team having 11 players. How many ways are there to do this ?
(A) 99
(B) 110
(C) 90
(D) 22
9. Define the following function : f(x, y) = (x+y) ÷ 2, g(x, y) = x2 – y2 and h(x, y) = (x – y) ÷ 2, Which of the followings has a value 0.25 for x = 0 and y = 0.5 ?
(A) f(x,y) g(x,y)
(B) g(x,y)
(C) f(x,y)
(D) f(x,y) + g(x,y)
10. A can do a piece of work in 10 days and B can do the same work in 20 days . With the help of C , they finish the work in 5 days . How many days will it take for C alone to finish the work ?
(A) 10 days
(B) 15 days
(C) 20 days
(D) 5 days
11. A Number x lies between 0 and 1. Which of the following is true ?
(A) x > √x
(B) x > 1/x
(C) x3 > x2
(D) 1/x > √x
12. The incomes of A and B are in ratio of 3 : 2 and their expenditure are in a ratio 5 : 3, If each saves Rs.1000, then B’s income is :
(A) Rs. 3000
(B) Rs. 4000
(C) Rs. 600
(D) Rs. 800
13. The speed of three cars are in ratio of 2 : 3 : 4. The ratio between the times taken by these cars to travel the same distance is :
(A) 2 : 3 : 4
(B) 4 : 3 : 6
(C) 3 : 4 : 6
(D) 6 : 4 : 3
14. After drawing the salary, a man deposit 10% of the sum in a bank and then paid 4% of the remainder as house rent. If he draws Rs.5000, the sum he paid as house rent is :
(A) Rs.160
(B) Rs.250
(C) Rs.180
(D) Rs.225
15. There are 100 question in the question paper each carrying 2 marks. But there is a negative marking; 1 mark is deducted from each question answered incorrectly. A student answering all the questions got 80 marks. The number of questions correctly answered by him is :
(A) 70
(B) 60
(C) 80
(D) 75
16. If 3 mangoes are sold for cost price of 4, the profit is :
(A) 16 1/3 %
(B) 33 1/4 %
(C) 33 1/2 %
(D) 40 1/2 %
17. The next term in the sequence 4, 10, 22, 46, … is
1. The least positive integer n such that n! divisible by 75 is
(A) 5
(B) 7
(C) 10
(D) 75
2. Two trains each of 200 metre length, and travelling with equal speed but in opposite directions, cross each other in 10 sec. The speed of the trains is.
(A) 18 km/hr
(B) 36 km/hr
(C) 20 km/hr
(D) 72 km/hr
3. A number, divisible by 7, which when divided by 4, 9 or 12 leaves a remainder 3. Then the number is
(A) 77
(B) 98
(C) 147
(D) 210
4. Ram was born 4 years after his father’s marriage. His mother is 6 years’ younger than his father but 25 years older than Ram, who is now 16 years old. At what age his father got married ?
(A) 25
(B) 27
(C) 29
(D) 31
5. In an examination 40% students fail in English, 30% in Mathematics and 15% in both. Then the pass percentage is
(A) 50%
(B) 30%
(C) 65%
(D) 45%
6. 2 oranges, 3 bananas and 4 apples taken together cost Rs.15.00. 3 oranges, 2 bananas and 1 apple cost Rs.10.00. Then the cost of 3 oranges, 3 bananas and 3 apples cost
(A) Rs.12.00
(B) Rs.16.00
(C) Rs.20.00
(D) Rs.15.00
7. Which of the triangles with the measures of sides given below is an obtuse-angled triangle ?
(A) (12, 5, 13) cm
(B) (6, 7, 5) cm
(C) (7, 3, 5) cm
(D) (8, 8, 8) cm
8. A rectangular field is half as wide as it is long, and its perimeter is p. The area of the field is
(A) p2/2
(B) 2p2
(C) p2/18
(D) 2p2/9
9. Mr. X has four children. His age equals to the sum of the ages of his four children. After 20 years his age will be half of his children’s combined age. Mr. X’s present age is
(A) 40 years
(B) 56 years
(C) 66 years
(D) 70 years
10. A dealer sold a radio for Rs.540 losing 10%. At what price should he have sold to earn a 10% profit ?
(A) Rs.660
(B) Rs.650
(C) Rs.600
(D) None of the above
11. If 15 apples and 20 oranges cost as much as 20 apples and 15 oranges, then which of the following conclusions is correct ?
(A) Orange and apple have equal price
(B) Orange is costlier
(C) Apple is costlier
(D) No conclusion can be made
12. The next term of the series
30, 42, 56, 72, ………
(A) 84
(B) 88
(C) 90
(D) 92
13. If the radius of a circle is increased by 100%, then the area of the circle will be increased by
(A) 100 %
(B) 200 %
(C) 300 %
(D) 400 %
14. Find the odd number out from the following series :
1. An alloy contains 20% zinc, 45% nickel and rest aluminium. The total mass in gm of the alloy containing 105 gm of aluminium is
(A) 170
(B) 200
(C) 250
(D) 300
2. 19 students appear in a class test. The average of the best 10 scores is 69 while that of the worst 10 is 38. If the average of all the 19 scores is 54, the 10th score in order of magnitude is
(A) 62
(B) 58
(C) 46
(D) 44
3. 50 added to 60% of a number is the number itself. The number is
(A) 110
(B) 125
(C) 200
(D) 300
4. The next term in the sequence
4, 5, 5, 5, 6, 5, 7 …………
(A) 5
(B) 6
(C) 7
(D) 8
5. Which number in the following sequence is incorrect ?
1, 4, 13, 40, 122, 364
(A) 13
(B) 40
(C) 122
(D) 364
6. In a college union election for the post of General Secretary, Surupa secured 60% of the total votes and defeated Ananya by a margin of 60 votes in a direct contest. Total number of valid votes was
(A) 120
(B) 150
(C) 300
(D) 360
7. Pinku babu purchased 4 baskets of mango containing 15, 18, 21 and 22 fruits. He kept the entire content of one of the baskets for his own family, and distributed the remaining mangoes equally among five of his friends living nearby. Number of mangoes in the basket he kept for his own family was
(A) 15
(B) 18
(C) 21
(D) 22
8. 69 biscuits were distributed among 27 students in a class. If each boy got 2 biscuits and each girl 3, how many girls were there in the class ?
(A) 23
(B) 19
(C) 15
(D) 12
9. The next term in the series
1, 2, 6, 15, 31, ____
(A) 47
(B) 50
(C) 56
(D) 63
10. Bidisha gets from her father Rs.50 every 30th day of a month and Rs.100 every 31st day. During 2008, she gets from her father a total of Rs.