O-LevelComputer ScienceBoolean logic2210/21 · May/June 2023 · Q98 Marks
Consider this logic expression. Z = (NOT A OR B) AND (B XOR C)
- (a)Draw a logic circuit for this logic expression. Each logic gate must have a maximum of two inputs. Do not simplify this logic expression. [Blank space with A, B, C inputs and Z output sketched][4]
- (b)Complete the truth table from the given logic expression. A | B | C | Working space | Z --|---|---|---------------|--- 0 | 0 | 0 | | 0 | 0 | 1 | | 0 | 1 | 0 | | 0 | 1 | 1 | | 1 | 0 | 0 | | 1 | 0 | 1 | | 1 | 1 | 0 | | 1 | 1 | 1 | | [4]
This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.
Mark scheme
Marking points from the official mark scheme (May/June 2023). The mark or mark type is shown in brackets.
- [1] (a) NOT gate for input A, output connected to OR gate
- [1] (a) OR gate with inputs from (NOT A) and B, output connected to AND gate
- [1] (a) XOR gate with inputs B and C, output connected to AND gate
- [1] (a) AND gate with inputs from OR and XOR gates, output Z (all gates correctly connected)
- [4] (b) Z column values: 0, 1, 1, 0, 0, 0, 1, 0 (4 marks for all 8 correct, 3 for 6/7, 2 for 4/5, 1 for 2/3 correct values)
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →