Data Representation Exam Practice

This lesson brings together all the key topics from the Data Representation unit and provides exam-style questions with model answers. Use this lesson to test your understanding and practise the types of questions you will face in the GCSE Computer Science exam.

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Topic Checklist

Before tackling exam questions, make sure you are confident with all of these topics:

• Converting between binary, denary, and hexadecimal
• Binary addition and overflow errors
• Binary shifts (left and right)
• ASCII and Unicode character encoding
• Representing images (resolution, colour depth, file size)
• Representing sound (sample rate, bit depth, file size)
• Units of data storage and conversions
• Lossy and lossless compression (including RLE)

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Exam-Style Questions with Model Answers

Question 1: Number Conversion (3 marks)

Convert the denary number 178 to an 8-bit binary number. Show your working.

Model Answer: