1.1 Data Representation

Question 1

What is the difference betwen a Binary prefix and a Decimal prefix?

Answer 1

A Binary prefix is based on powers of 2.

A Decimal prefix is based on powers of 10.

Question 2

How many bytes in a Kibibyte?

Answer 2

1024

Question 3

How many bytes in a Mebibyte?

Answer 3

1024**2

Question 4

How many bytes in a Gibibyte?

Answer 4

1024**3

Question 5

How many bytes in a Tebibyte?

Answer 5

1024**4

Question 6

What is 24 in Binary?

Answer 6

11000

Question 7

What is 244 in Hexadecimal?

Answer 7

1) Convert to binary
1111 0100
2)Convert from Binary to Hexadecimal
F4

Question 8

Turn 25 into a Binary Coded Decimal (BCD).

Answer 8

00100101

Question 9

Convert the Denary number -100 into Two’s Complement Binary.

Answer 9

10011100

Question 10

Convert the One’s Complement negative binary integer 10110110 into denary.

Answer 10

1) Invert all the Bits
01001001
2) Turn to denary
-73

Question 11

Using Binary Addition, calculate 10111 + 100110.

Answer 11

111101

Question 12

Using the rules of binary subtraction,

calculate 11010 - 101.

Answer 12

1) Normalise, 00101
2) Flip, 11010
3) Add 1, 11011

11010 + 11011 = 110101
4) Discard first bit / Overflow error
10101

Question 13

How does overflow occur?

Answer 13

When the result of an arithmetic operation creates a value that exceeds the range represented by the allocated number of bits.

Question 14

Applications of Hexadecimal.

Answer 14

• Assembly language programming to represent instructions in program code.
• Graphic packages to represent colour codes.
• Program code to represent characters.

Question 15

Applications of BCD.

Answer 15

Used in electronic systems where a string of digits is used to represent some value.

Question 16

Difference between ASCII and Unicode?

Answer 16

• Unicode is a superset of ASCII
• ASCII is stored in 8 bits
• Unicode supports all the languages in the world whereas ASCII only supports English.