Oxford Cambridge and RSA
Examinations GCSEComputer
ScienceJ277/01: Computer
systemsGeneral Certificate of
Secondary Education with
marking scheme
, Oxford Cambridge and RSA
Friday 19 May 2023 – Afternoon
GCSE (9–1) Computer Science
J277/01 Computer Systems
Time allowed: 1 hour 30 minutes
Do not use:
* 9 9 3 2 3 6 4 5 2 6 *
• a calculator
* J 2 7 7 0 1 *
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
INFORMATION
• The total mark for this paper is 80.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 16 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2023 [601/8355/X] OCR is an exempt Charity
DC (PQ) 325517/4 Turn over
, 2
1 Computers represent data in binary form.
(a) Tick (3) one box to identify the statement about binary that is true.
Binary digits can only be the values 0, 1 and 2
The left-most bit of a binary integer has the smallest value
Binary is used because computers are made of switches that can only be on or off
The smallest whole number that can be stored in 8 bits is the number 1
[1]
(b) Complete the table by writing the missing denary, 8-bit binary or hexadecimal values.
Denary 8-bit binary Hexadecimal
00000111 7
49 31
01100110 66
244 11110100
[4]
© OCR 2023
, 3
(c) Tick (3) one box to identify the largest file size.
2 000 000 bytes
2300 KB
200 MB
0.1 GB
[1]
(d) Tick (3) two boxes to identify the two file sizes that are equal to each other.
4 500 000 bytes
450 KB
4.5 MB
0.45 GB
[1]
(e) Complete the binary addition by adding these two 8-bit binary numbers.
Show all your working.
0 1 1 1 0 0 0 1
+ 1 0 0 1 1 1 1 0
[2]
(f) Identify the binary shift that has been applied to the 8-bit binary number 10110000 to get the
result 10000000.
...................................................................................................................................................
.............................................................................................................................................. [2]
© OCR 2023 Turn over
Examinations GCSEComputer
ScienceJ277/01: Computer
systemsGeneral Certificate of
Secondary Education with
marking scheme
, Oxford Cambridge and RSA
Friday 19 May 2023 – Afternoon
GCSE (9–1) Computer Science
J277/01 Computer Systems
Time allowed: 1 hour 30 minutes
Do not use:
* 9 9 3 2 3 6 4 5 2 6 *
• a calculator
* J 2 7 7 0 1 *
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
INFORMATION
• The total mark for this paper is 80.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 16 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2023 [601/8355/X] OCR is an exempt Charity
DC (PQ) 325517/4 Turn over
, 2
1 Computers represent data in binary form.
(a) Tick (3) one box to identify the statement about binary that is true.
Binary digits can only be the values 0, 1 and 2
The left-most bit of a binary integer has the smallest value
Binary is used because computers are made of switches that can only be on or off
The smallest whole number that can be stored in 8 bits is the number 1
[1]
(b) Complete the table by writing the missing denary, 8-bit binary or hexadecimal values.
Denary 8-bit binary Hexadecimal
00000111 7
49 31
01100110 66
244 11110100
[4]
© OCR 2023
, 3
(c) Tick (3) one box to identify the largest file size.
2 000 000 bytes
2300 KB
200 MB
0.1 GB
[1]
(d) Tick (3) two boxes to identify the two file sizes that are equal to each other.
4 500 000 bytes
450 KB
4.5 MB
0.45 GB
[1]
(e) Complete the binary addition by adding these two 8-bit binary numbers.
Show all your working.
0 1 1 1 0 0 0 1
+ 1 0 0 1 1 1 1 0
[2]
(f) Identify the binary shift that has been applied to the 8-bit binary number 10110000 to get the
result 10000000.
...................................................................................................................................................
.............................................................................................................................................. [2]
© OCR 2023 Turn over
