OCR
GCSE
Computer Science
J277/01: Computer systems
Merged Question Paper + Mark Scheme
Ace your Mocks!!!
, Oxford Cambridge and RSA
Wednesday 15 May 2024 – Afternoon
GCSE (9–1) Computer Science
J277/01 Computer Systems
Time allowed: 1 hour 30 minutes
Do not use:
* 1 4 2 6 5 6 2 7 6 3 *
• 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.
, 2
1
(a) The following table has either the binary or denary value of 3 numbers.
Complete the table by converting the 8-bit binary number into denary and the denary number into
8-bit binary.
8-bit Binary Denary
11110000
105
00011110
[3]
(b) Complete the table by writing the answer to each statement.
Statement Answer
The smallest denary number that can be
represented by a 4-bit binary number
The largest denary number that can be
represented by a 6-bit binary number
The maximum number of different colours
that can be represented with a colour depth of
7-bits
The minimum number of bits needed to
represent 150 different characters in a
character set
[4]
(c) Show the result of a left binary shift of 4 places on the binary number 00001111.
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