1.The number 0 is

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    (A) whole number but not integer.

    (B) integer but not rational.

    (C) rational but not real number.

    (D) whole number, integer, rational and real number

2. π and 22⁄7 are 

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(A) both are rational number.

  (B) both are always irrational number.

   (C) π is rational and 22⁄7 is irrational.

   (D) π is irrational and 22⁄7 is rational

3.The sum of first five prime number is

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 (A) 11     

 (B) 18     

 (C) 26    

 (D) 28

4.The number 7–√

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(A) lies between 1 and 2

(B) lies between 2 and 3

(C) lies between 3 and 4

(D) lies between 6 and 7

5.123456789 x 8 + 9 is equal to

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(A) 98765431    

 (B) 89765431     

 (C) 987654321  

 (D) None of the above

6. 11111 x 11111 is equal to

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 (A) 111111111   

  (B) 123454321       

(C) 54321321      

  (D) 14325321

7.A student was asked to divide a number by 3. But, instead of dividing it, he multiplied it by 3 and got 29.7. What was the correct answer ?

WBCS- main2017

  (A) 9.3    

   (B) 3.3   

   (C) 9.8  

     (D) 9.9

8.How many digits are required for numbering the pages of a book having 300 pages ?

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 (A) 299    

 (B) 492      

 (C) 789     

  (D) 792

1.If the difference between two numbers is 5 and the difference between their cubes is 1850, then the difference between their squares is:

যদি দুটি সংখ্যার পার্থক্য  5 হয় এবং তাদের ঘনের পার্থক্য 1850 হয় তাহলে তাদের বর্গের পার্থক্য কত?

 SSC CHSL-2021

a) 5√484

b) 5√482

c) 5√485

d) 5√483

2.Of four numbers, the second number is 20% more than the first, the third is 10% less than the second and the fourth number is 50% more than the third. If the fourth number is 405, find all the numbers.

 চারটি সংখ্যার মধ্যে, দ্বিতীয় সংখ্যাটি প্রথমটির চেয়ে 20% বেশি, তৃতীয়টি দ্বিতীয়টির থেকে 10% কম এবং চতুর্থ সংখ্যাটি তৃতীয়টির চেয়ে 50% বেশি। যদি চতুর্থ সংখ্যাটি 405 হয় তবে সংখ্যাগুলি হল -

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(A) 300, 405, 250, 270     

 (B) 300, 270, 405, 250     

  (C) 275, 290, 310, 380      

 (D) 250, 300, 270, 405 

9.The number of coconuts plucked from each tree is 1 more than the number of coconut trees in Anil's garden. The total number of coconut plucked is 132. The total number of coconut trees in the garden is

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  (A) 12   

  (B) 22 

  (C) 11

   (D) 33

10.The sum of digits of a two-digit number is 12. When the digits are interchanged, the resulting number is 36 more than original number. What is the original two-digit number ?

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 (A) 93   

 (B) 48   

 (C) 39      

 (D) 84

11.The sum of three consecutive multiples of 3 is 72. What is the largest number ?

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 (A) 21 

 (B) 24   

  (C) 27   

  (D) 36

12.If the product of two successive positive integers is 7482. which is the greatest integer ?

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 (A) 87      

(B) 82     

 (C) 8.4    

   (D) 89

13.A man saved Rs. 16,500 in 10 years. In each year after the first year he saved Rs. 100 more than he did in the preceding year. How much did he save in the first year ?

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  (A) Rs.1200    

  (B) Rs.1650     

 (C) Rs.1000    

  (D) Rs.1020

14. If the sum of two numbers is 10 and the sum of their reciprocals is 5⁄₁₂ , the numbers would be-

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  (A) (8, 2)  

  (B) (6, 4)       

 (C) (7, 3)      

  (D) (9, 1)

15. The product of two successive numbers is 1980. The smaller number is -

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  (A) 34    

   (B) 35     

  (C) 44        

(D) 45

16 .4⁄₅  of a certain number is 64. Half of the number-

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 (A) 32    

 (B) 40    

 (C) 80       

 (D) 16

17.A boy was asked to multiply a number by 12. By mistake he multiplied the number by 21 and got his answer 63 more than the correct answer. The answer was

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  (A) 8    

   (B) 7    

   (C) 12    

   (D) 9

18.The product of two numbers is 1575 and its division is 7⁄₉ .Then the two numbers are

WBCS-2016

    (A) 45,  35  

    (C) 35,  27  

    (B) 81, 63   

    (D) 36, 35

19. The sum 5 + 6 + 7 + 8 + ........... + 19 = ?

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 (A) 150     

 (B) 170    

 (C) 180  

  (D) 190

20.The difference of 1³⁄₁₆ and its reciprocal is -

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 (A)   1¹⁄₈  

(B)  1¹⁄₃   

(C) ¹⁵⁄₁₆   

(D) ¹⁰⁵⁄₃₀₄

 21.. A student was asked to divide a number by 3, but instead of dividing it, he multiplied it by 3 and got 29.7. The correct answer was -

WBCS-2016

  (A) 3.3     

   (B) 9.3    

    (C) 9.8    

    (D) 9.9

22.How many digits are required for numbering the pages of a book having 300 pages ?

WBCS-2015

  (A) 299   

   (B) 492    

   (C) 789    

    (D) 792

23.No of Zeros in the product of natural numbers from 1 to 10 will be

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     (A) 4       (B) 3       (C) 2       (D) 1

24.The sum of first five multiple of 3 is

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a) 45

b) 65

c) 54

d)52

25.In a two digit number, the unit's digit

exceeds ten's digit by 2 and the product of the sum of the digits and the number is 144, then what is the number?

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(A) 24

(B) 02

(C) 68

(D) 46

26.The number of multiples of 4 between 10

and 250 is

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(A) 50

(B) 40

 C) 60

(D) 30

27.The number of coconuts plucked from each tree is 1 more than the number of coconut trees in Anil's garden. The total number of coconut plucked is 132. The total number of coconut trees in the garden is

WBCS-2021

(A) 12

(B) 22

(e) 11

(D) 33

28.Consider the pairs of prime numbers (m, n) between 50 and 100 such that m - n = 6. How many such pairs are there?

CDS-2021

(a) 2

(b) 3

(c) 4

(d) 5

29.If 1⁄_1x2+ 1⁄_2x3+ 1⁄_3x4 +...........+ 1⁄_nx(n+1)+=99⁄₁₀₀

then what is value of n?

CDS-2021

a) 98

b)99

c) 100

d)101

30.The sum of the reciprocals of two alternate natural numbers is 7⁄₂₄ What is the sum of the numbers?

CDS-2021

(a) 12

(b) 13

(c) 14

(d) 16

31.The number 2×3×5x7x11+1 is

CDS-2020

(a) a prime number

(b) not a prime, but power of a prime

(c) not a power of a prime, but a composite even number

(d) not a power of a prime, but a composite odd number

32.Which one of the following number is largest number among

 2222 ² ,222 ²², 22 ²²²,2 ²²²²

CDS-2020

a) 2222 ²

b) 222 ²²

^c)  22 ²²²

d) 2 ²²²²

33.If m is the number of prime numbers..between 0 and 50; and is the number of prime numbers between 50 and 100, then what is (m-n) equal to ?

CDS-2020

(a) 4

(b) 5

(c) 6

(d) 7

34.If 10 ⁿ  divides 6²³ x 75⁹ x105 ² , then

what is the largest value of n?

CDS-2019

(a) 20
(b) 22
(c) 23
(d) 28
35. What is the digit in the unit's place of
the number represented by  3⁹⁸-3⁸⁹ ?

CDS-2019
(a) 3
(b) 6
(c) 7
(d) 9

36.Consider the following statements:

1. Unit digit in 17¹⁷⁴ is 7.

2.Difference of the squares of any two odd numbers is always divisible by 8.

3. Adding 1 to the product of two consecutive odd numbers makes it a perfect square.

Which of the above statements are correct?

CDS-2019

(a) 1, 2 and 3

(b) 1 and 2 only

(c) 2 and 3 only

(d) 1 and 3 only

37.24. When N is divided by 17, the quotient is equal to 182. The difference between the quotient and the remainder is 175. What is the value of N?

CDS-2019

(a) 2975

(b) 3094

(c) 3101

(d) 3269

38.What is the remainder when (1729 + 1929) isdivided by 18 ?

(a) 6
(b) 2
(c)
(d) 0
What is the largest value of n such that 10⁰
divides the product
25 x 33 x 48 x 53 x 67 x 76 x 812 x 99 x
(a)
1
(b)
(c)
65
55
r
50
(d) 45
(c)
How many pairs (A, B) are possible in the
number 479865AB if the number is divisible
by 9 and it is given that the last digit of the
number is odd ?
(a) 5
(b) 6
9
106 1512 2014 x 2211 x 2515?
(d) 11

7⁄₉

 5⁄₁₂

33¹⁄₃

1¹⁄₈

22  

7