FPSC- Programmer (BS-17) - Pakistan Meteorological Department (PMD) Model Papers - 2026 — Part 3 (100 Q)

Correct Answer: D. (NOT A) OR (NOT B)
Explanation: Negating a conjunction gives the disjunction of the negations. Changing only the operator (or only the operands) is a common mistake. ALSO KNOW (related points): • How many rows does a complete truth table for 4 input variables have? → 16

Correct Answer: B. A
Explanation: This is the absorption law: A + AB = A(1 + B) = A.

Correct Answer: C. A + B
Explanation: A + A'B = (A + A')(A + B) = 1·(A + B) = A + B. ALSO KNOW (related points): • Simplify the Boolean expression A + AB. → A • Simplify (A AND B) OR (A AND NOT B). → A

Correct Answer: A. 1
Explanation: Group it as (1 XOR 1) XOR 1 = 0 XOR 1 = 1. A chain of XORs is 1 exactly when an odd number of the inputs are 1.

Correct Answer: C. NAND
Explanation: NAND and NOR are both universal. AND, OR, and XOR cannot produce NOT by themselves. ALSO KNOW (related points): • What does a NOR gate output when both of its inputs are 0? → 1 • In C, what is the value of x ^ x for any int x? → 0

Correct Answer: B. 1
Explanation: NOR = NOT(A OR B). With both inputs 0, A OR B is 0, so the output is 1.

Correct Answer: B. 16
Explanation: There are 2^n rows for n variables, so 2^4 = 16.

Correct Answer: D. x <= 5 || y >= 3
Explanation: Apply De Morgan's law: switch && to ||. Also note that the negation of > is <=, not <. ALSO KNOW (related points): • How many select lines does a 4-to-1 multiplexer need? → 2

Correct Answer: D. (NOT A) OR B
Explanation: An implication is false only when A is true and B is false, which matches NOT A OR B.

Correct Answer: D. Only when P is true and Q is false
Explanation: When P is false, the implication is vacuously true.