Binary, denary and hexadecimal patterns represent numbers.
Convert the denary number -46 to 8-bit binary using two's complement.
Mark scheme
Award one mark for each correct nibble in the correct order:
- 1101 (1)
- 0010 (1)
0 marks if the response is not 8-bit binary.
Example answers and how they were marked
Full marks2/2
1101 0010
Why: 46 is 00101110; flip the bits (11010001) and add 1: both nibbles are correct (2).
Some marks1/2
1101 0001
Why: Flips the bits of 46 but doesn't add 1. The first nibble is correct (1); the second is not.
No marks0/2
1010 1110
Why: Uses sign and magnitude (a 1 in front of 46) instead of two's complement. Neither nibble is correct.