Computer Fundamentals (Number System)

1. The digital systems usually operate on ........system.

(a) binary

(b) decimal

(c) octal

(d) hexadecimal.

2. The binary system uses powers of ........for positional values.

(a) 2

(b) 10

(c) 8

(d) 16

3. After counting 0, 1, 10, 11, the next binary number is

(a) 12

(b) 100

(c) 101

(d) 110.

4. The number 1000₂ is equivalent to decimal number

(a) one thousand

(b) eight

(c) four

(d) sixteen.

5. In binary numbers, shifting the binary point one place to the right.

(a) multiplies by 2

(b) divides by 2

(c) decreases by 10

(d) increases by 10.

6. The binary addition 1 + 1 + 1 gives

(a) 111

(b) 10

(c) 110

(d) 11

7. The cumulative addition of the four binary bits ( 1 + 1 + 1 + 1) gives

(a) 1111

(b) 111

(c) 100

(d) 1001

8. The result of binary subtraction (100 − 011) is

(a) −111

(b) 111

(c) 011

(d) 001.

9. The 2's complement of 1000₂ is

(a) 0111

(b) 0101

(c) 1000

(d) 0001

10. The chief reason why digital computers use complemental subtraction is that it

(a) simplifies their circuitry

(b) is a very simple process

(c) can handle negative numbers easily

(d) avoids direct subtraction.

11. The result of binary multiplication 111₁ × 10₂ is

(a) 1101

(b) 0110

(c) 1001

(d) 1110

12. The binary division 11000₂ ÷ 100₂ gives

(a) 110

(b) 1100

(c) 11

(d) 101

13. The number 128 is equivalent to decimal

(a) 12

(b) 20

(c) 10

(d) 4

14. The number 100101₂ is equivalent to octal

(a) 54

(b) 45

(c) 37

(d) 25.

15. The number 178 is equivalent to binary

(a) 111

(b) 1110

(c) 10000

(d) 1111.

16. Which of the following is NOT an octal number?

(a) 19

(b) 77

(c) 15

(d) 101

17. Hexadecimal number system is used as a shorthand language for representing .......numbers.

(a) decimal

(b) binary

(c) octal

(d) large

18. The binary equivalent of A16 is

(a) 1010

(b) 1011

(c) 1000

(d) 1110.

19. BCD code is

(a) non-weighted

(b) the same thing as binary numbers

(c) a binary code

(d) an alphanumeric code.

20. Which of the following 4-bit combinations is/are invalid in the BCD code ?

(a) 1010

(b) 0010

(c) 0101

(d) 1000.

21. Octal coding involves grouping the bits in

(a) 5's

(b) 7's

(c) 4's

(d) 3's.

22. In Excess-3 code each coded number is .......than in BCD code.

(a) four larger

(b) three smaller

(c) three larger

(d) much larger.

23. Which numbering system uses numbers and

letters as symbols ?

(a) decimal

(b) binary

(c) octal

(d) hexadecimal

24. To convert a whole decimal number into a hexadecimal equivalent, one should divide the

decimal value by.......

(a) 2

(b) 8

(c) 10

(d) 16.

Answers

1. (a) 2. (a) 3. (b) 4. (b) 5. (a) 6. (d) 7. (b) 8. (d) 9. (c) 10. (a) 11. (d) 12. (a) 13. (c) 14. (b) 15. (d) 16. (a) 17. (a) 18. (a) 19. (c) 20. (a) 21. (d) 22. (c) 23. (d) 24. (a)