27 Oct
Latest
QuestionsA Level
Unit 1 — Computer systems
Verified production counts for main topics 1.1, 1.2, 1.3, 1.4.
825 improved · 891 new · 565 retired
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OCR GCSE J277 and A Level H446
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27 Oct
QuestionsA LevelUnit 2 — Algorithms and programming
Verified production counts for main topics 2.1, 2.2, 2.3.
16 improved · 904 new
20 Oct
Revision notesA Level47 knowledge organisers revised
Revised A Level notes, including new diagrams.
Including The Fetch-Decode-Execute cycle, Virtual storage and Linkers and loaders and use of libraries and 44 more.
20 October 2026
Teachers: retired questions are skipped automatically for students who haven't answered them yet. Answers already given are kept.
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GCSE · OCR J277
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revisecomputing.co.uk/questions/data-representation
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Data Representation
Question
What is the denary value of the binary number 1011?
Model Answer
Correct Answer:
11
To convert binary 1011 to denary: (1 × 2³) + (0 × 2²) + (1 × 2¹) + (1 × 2⁰) = 8 + 0 + 2 + 1 = 11
A Level · OCR H446
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