## RRB Railway NTPC Aptitude **NUMBER SYSTEM **Quiz

**1) Minimum difference between x and y such that 1x71y 61 is exactly divisible by 11 is,**

(a) 2

(b) 3

(c) 1

(d)0

**2. The four integers next lower than 81, and the four next higher than 81, are written down and added together, this sum is divisible by,**

(a) 7

(b) 9

(c) 11

(d) 13

**3. If‘n’ is a natural number then the greatest integer less than that or equal to (2+√3)^n is**

(a) odd

(b) even

(c) even when ‘n’ is even and odd when ‘a’ is odd

(d) even when ‘n’ is odd and odd when n is even

**4. How many numbers, between 1 and 300 are divisible by 3 ‘ and 5 together?**

(a) 16

(b) 18

(c) 20

(d) 100

**5. What is the remainder when 1! + 2! + 3! + …+100! is divided by 7 ?**

(a) 0

(b) 5

(c) 6

(d) 3

**6. How many numbers, lying between 1 and 500, are divisible by 13?**

(a) 40

(b) 38

(c) 41

(d) 46

**7. Two different numbers when divided by the same divisor, left remainder 11 and 21 respectively, and when their sum was divided by the same divisor, remainder was 4. What is the divisor?**

(a) 36

(b) 28

(c) 14

(d) 9

**8. A number when divided by a divisor, left remainder 23. When twice of the number was divided by the same divisor, remainder was 11. Find the divisor.**

(a) 12

(b) 34

(c) 35

(d) data inadequate

**9. A number when divided by 5 leaves a remainder 3. What is the remainder when the square of the same number is divided by 5?**

(a) 9

(b) 3

(c) 0

(d) 4

**10. The value of 3÷[(8-5)+{(4-2)+(2+8/13) } ]**

(a) 15/17

(b) 13/17

(c) 15/19

(d) 13/19

**11. A number when successively divided by 7 and 8 leaves the remainders 3 and 5 respectively. What is the remainder when the same number is divided by 56?**

(a) 38

(b) 31

(c) 37

(d) 26

**12. A boy wanted to write the numbers from the smallest number to the greatest number of three digits. How many times he needs to press the keys of the computer to do this job?**

(a) 2708

(b) 2889

(c) 2644

(d) 2978

**13. A number, being successively divided by 3, 5 and 8 leaves 1,2 and 4 as remainders respectively. What are the remainders if the order of divisors be reversed?**

(a) 3, 3, 1

(b) 3, 1, 3

(c) 1, 3, 3

(d) None of these

**14. The numbers 1 to 29 are written side by side as follows1234567891011……2829**

**If the number is divided by 9, then what is the remainder?**

(a) 3

(b) 1

(c) 0

(d) None of these

**15. If x 959 y is divisible by 44 and y >5, then what are values of the digit x and y?**

(a) x = 7, y = 6

(b) x = 4, y = 8

(c) x = 6, y = 7

(d) None of these

**16. When (1/2-1/4+1/5-1/6) is divided by (2/5-5/9+3/5-7/18)the result is:**

(a) 2 1/18

(b) 31/6

(c) 33/10

(d) 51/10

**17. A boy multiplied a certain number x by 13. He found that the resulting product consisted of all nines entirely. Find the smallest value of x.**

(a) 76913

(b) 76933

(c) 76923

(d) 75933

**18. A number is successively divided by 5,6,8; leaving remainders 3,4,7 respectively. What will be the remainders if the order of divisors be reversed?**

(a) 7,4,3

(b) 5,3,4

(c) 2,5, 4

(d) 1, 5,4

**19. A certain number is divided by 385 by division by factors. The quotient is 102, the first remainder is 4, the second is 6 and the third is 10. Find the number.**

(a) 39654

(b) 32754

(c) 38554

(d) None of these

**20. Two numbers when divided by a certain divisor leave the remainders 4375 and 2986 respectively; but when the sum of the two numbers be divide ‘by the same divisor, the remainder is 2361. The divisor is**

(a) 2014

(b) 5000

(c) 625

(d) 2639