Numbers Worksheet-5

Numbers Worksheet-5

1. Factor × factor is equal to

(a) difference    (b) multiple       (c) sum               (d) none

2. Every number is a ____ and a ____ of itself.

(a) factor, multiple                       (b) prime, composite

(c) even, odd                                  (d) none

3. The numbers which are multiples of 2 are called

(a) odd               (b) even              (c) prime           (d) composite

4. Which of the following number is even?

(a) 10351            (b) 20989          (c) 69007          (d) 973572

5. A number which is a factor of every number is

(a) 0                    (b) 1                    (c) 2                    (d) None

6. Number of prime numbers from 1 to 50 are

(a) 18                  (b) 12                  (c) 15                   (d) 20

7. Difference between a prime (19) and a composite (25) number is

(a) 6                    (b) 8                    (c) 9                    (d) 3

8. The prime number which comes just after 43 is

(a) 49                  (b) 45                  (c) 47                  (d) None

9. Number of prime numbers between 50 to 60 is

(a) 1                     (b) 2                    (c) 3                    (d) 4

10. 20 is written as the product of primes as

(a) 2 × 5                                          (b) 2 × 2 × 3 × 5

(c) 2 × 2 × 5                                   (d) 2 × 2 × 3

11. Prime factors of 140 are

(a) 2 × 2 × 7                                   (b) 2 × 2 × 5

(c) 2 × 2 × 5 × 7                            (d) 2 × 2 × 5 × 7 × 3

12. HCF of 24, 36 and 92 is

(a) 24                  (b) 36                 (c) 12                  (d) 4

13. LCM of 81, 18 and 36 is

(a) 81                  (b) 162                (c) 324               (d) 36

14. Successor of every even number is

(a) even              (b) prime           (c) odd                (d) none

15. Example for co-prime numbers is

(a) 25, 14           (b) 18, 16            (c) 9, 18              (d) 11, 77

16. Choose the co-prime numbers from the following pairs.

(a) 7 and 63                                   (b) 36 and 25

(c) 35 and 21                                 (d) 63 and 81

17. The sum of the first five multiples of 6 is

(a) 90                 (b) 60                 (c) 30                  (d) 120

18. The smallest number which when divided by 20, 25, 35 and 40 and leaves a remainder of 14, 19, 29 and 34 respectively is

(a) 1394             (b) 1404             (c) 1664              (d) 1406

19. The LCM of two numbers is x and their HCF is y. The product of two numbers is

(a)                   (b)                   (c) x + y              (d) Xy

20. The least number which when divided by 9, 12, 16, 30 leaves in each case a remainder of 3 is

(a) 720               (b) 723               (c) 823               (d) 750

Answer Key:

(1)-(b); (2)-(a); (3)-(b); (4)-(d); (5)-(b); (6)-(c); (7)-(a); (8)-(c); (9)-(b); (10)-(c); (11)-(c); (12)-(d); (13)-(c); (14)-(c); (15)-(a); (16)-(b); (17)-(a); (18)-(a); (19)-(d); (20)-(b)