ASCII is a character set used for representing text.
Identify the number of bits used to encode each character in ASCII.
Mark scheme
- B 7 (1)
- The only correct answer is B. The correct answer is 7 bits.
- A is not correct because 6 bits give only 64 different characters
- C is not correct because 8 bits are used by extended ASCII to give 256 characters
- D is not correct because 16 bits give 65 536 different characters, which is far more than the 128 in ASCII
Example answers and how they were marked
Full marks1/1
B 7
Why: B is the only correct answer: each ASCII character is encoded using 7 bits (1).
No marks0/1
C 8
Why: Near miss scoring 0: 8 bits is extended ASCII, and the scheme's C line says extended ASCII, not ASCII, is not the answer.
No marks0/1
A 6
Why: Misconception scoring 0: 6 bits give only 64 different characters, so it cannot be ASCII.