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OCR H446 1.4.1 Data representation exam transition
Part 11 of 11 · H446 1.4.1 · Data types
An assessment piece for the end of H446 1.4.1, worked independently and without checking answers along the way. An original satellite-media scenario samples the whole specification point, from type choice and base conversion through signed arithmetic, floating-point addition, shifts, masks and character sets, so a teacher can see which method a student reaches for unprompted.
Students will:
- state suitable primitive data types for values in an unfamiliar scenario
- complete mixed 8-bit binary, hexadecimal and denary conversions without prompts
- represent and correct signed values in 8-bit two's complement, showing the method
- align, calculate and normalise an OCR-format floating-point addition
- review their own evidence and name the method to revisit before a timed assessment
Inside: 1 explanation cell, 5 written answers and 5 number answers. 40 marks, about 55 to 70 minutes.
Series: H446 1.4.1 · Data types, part 11 of 11.
Shared by Coding PathwayVerified teacher
- 11 cells
- About 60 minutes
- CC BY-SA 4.0
- Shared 31 Aug 2026
- Updated 3 Sept 2026
Preview
The whole resource, exactly as a class sees it. Answers and marking are held back.
Data representation exam transition
Complete this assessment independently and without checking answers as you go. Use the command words, supplied evidence and context carefully; correctness is held where the platform supports it.
This original satellite-media scenario samples OCR H446 1.4.1. Feedback is withheld for teacher review and there is no teaching between questions.
Readiness check before starting
You should already be able to choose a primitive type, convert bases, represent signed integers, show binary arithmetic, align and normalise OCR floating-point values, apply shifts/masks and use a supplied character mapping. ## Exam routine
Name the representation and width → show the method → give the result → add interpretation when asked. A result and its purpose may earn separate marks.
A payload record stores file_name = 'aurora-07', retry_count = 3 and signal_valid = True. State the most suitable primitive data type for each value.
Use OCR data-type names.
Students type their answer here.
Complete the mixed 8-bit binary, hexadecimal and denary payload identifiers.
a)Denary 212. Fill in the binary and hexadecimal.
b)Binary 10101111. Fill in the denary and hexadecimal.
c)Binary 00101101. Fill in the denary and hexadecimal.
d)Denary 103. Fill in the binary and hexadecimal.
Represent each signed reading as an 8-bit two's-complement integer. Show the method.
a)Write −59 as an 8-bit two's complement number.
b)Write −90 as an 8-bit two's complement number.
c)Write −112 as an 8-bit two's complement number.
Complete each 8-bit two's-complement correction. Show the method.
a)Use two's complement to work out 01111101 − 00001110.
b)Use two's complement to work out 00011010 − 00010100.
Add the OCR-format floating-point signal adjustments. Align exponents, calculate the mantissa and normalise the result.
Add the floating point numbers 011100 (exponent 1110) and 010001 (exponent 1111). Give a normalised answer.
Explain why aligning two floating-point values before addition can reduce the precision of the final result.
Refer to a fixed-width mantissa.
Students type their answer here.
Apply each logical shift to the 8-bit payload control value and state its denary effect.
a)Apply a logical shift right of 2 places to 00011101.
b)Apply a logical shift right of 2 places to 11110110.
c)Apply a logical shift right of 2 places to 10001111.
The status byte 10101100 is ANDed with 00001111. Give the result and explain the purpose of the mask.
The result and purpose are marked separately.
Students type their answer here.
A payload initially supports basic English text but later needs scientific symbols and many writing systems. Compare ASCII with Unicode and recommend one for the later system.
Use the scenario and avoid fixed-width claims about all Unicode encodings.
Students type their answer here.
Which method should you revisit before a timed assessment, and what evidence from your answers supports that choice?
This reflection is not assessed.
Students type their answer here.