3.3 - data representation (1-4)

Question 1

for the following number bases, what are they to the base of?

a) decimal
b) binary
c) hexadecimal

Answer 1

a) base 10
b) base 2
c) base 16

Question 2

benefits of hexadecimal

and give an example of what a hexadecimal value looks like

Answer 2

• numbers are shorter
• easier to read + write (reducing the chance of errors)

AD

Question 3

what do computers use binary for?

Answer 3

to represent all data and instructions

Question 4

what kind of data can a bit pattern represent?

Answer 4

text, image, sound, integer

Question 5

write down all the characters in hexadecimal (and the denary equivalent)

Answer 5

0-9 all are 0 to 9

10 to 15 are A to F
not case sensitive

Question 6

what is slightly strange about hexadecimal?

hint number of characters

Answer 6

it is called base 16

but the numbers only go up to 15, as they count 0 as a number

Question 7

when converting between denary and binary what are the numbers at the top of the table?

Answer 7

128 64 32 16 8 4 2 1

Question 8

what is a bit?

Answer 8

the fundamental unit of information (ie. either a 0 or 1)

Question 9

what is a byte?

Answer 9

a group of 8 bits

Question 10

what symbol represents a bit, which represents a byte?

Answer 10

b = bit 
B = byte

Question 11

what is a nibble?

Answer 11

half a byte (4 bits)

- like sounds exactly as it is

Question 12

in terms of bytes, what is a kilobyte?

Answer 12

a kilobyte is 1000 bytes

Question 13

draw out the table which shows how many bites are corresponding to the previous one?
(MB - GB - TB)

Answer 13

1MB = 1000KB
1GB = 1000MB
1TB = 1000GB

Question 14

add the following binary numbers:
- 1101011

• 0001011

Answer 14

1  1  0 1 0  1  1 
\+  0 0 0 1 0 1  1 
------------------------
    1  1 1  0 1  1  0
-------------------------
           1     1  1

Question 15

if a value is said to left shift by 16, how many places does it move?

Answer 15

x 4

2 4 8 16

Question 16

if a value is said to right shift by 8, how many places does it move?

Answer 16

divided by 3

2 4 8

Question 17

when are binary shifts used?

Answer 17

perform simple multiplication/ division by powers of 2