A-LevelComputer ScienceHardware9618/31 · Oct/Nov 2022 · Q77 Marks

Complete the Karnaugh map (K-map) for the Boolean expression. Z = Ā. B. C. D + Ā. B. C. D + A. B. C. D + A. B. C. D + A. B. C. D + A. B. C. D AB 00 01 11 10 CD 00 01 11 10

(a)Complete the Karnaugh map (K-map) for the Boolean expression. Z = Ā. B. C. D + Ā. B. C. D + A. B. C. D + A. B. C. D + A. B. C. D + A. B. C. D AB 00 01 11 10 CD 00 01 11 10[2]
(b)Draw loop(s) around appropriate group(s) in the K-map to produce an optimal sum-of-products.[2]
(c)Write the Boolean expression from your answer to part (b) as a simplified sum-of-products. Use Boolean algebra to give your answer in its simplest form. Simplified sum-of-products Z = Simplest form Z =[3]

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Mark scheme

Marking points from the official mark scheme (Oct/Nov 2022). The mark or mark type is shown in brackets.

[2] Two marks if no errors present, One mark if one error present
AB 00 01 11 10 CD 00 0 1 1 1 01 0 1 1 1 11 0 0 0 0 10 0 0 0 0
[2] One mark for correct loop (Max 2)
[3] One mark for each point: Any correct Boolean term, Boolean terms and operator correct and no other terms present, One mark for simplest form
(Z =) BC + AC
(Z =) C (A + B)

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