OR gate outcomes A 3-input OR gate has eight possible input combinations. For how many combinations will the output be logic HIGH?

Introduction / Context:
Understanding OR gate behavior across all input states is foundational for designing combinational logic and estimating probabilities of output activity.

Given Data / Assumptions:

• Inputs: 3 binary inputs → 2^3 = 8 combinations.
• OR function: output is 1 if any input is 1.

Concept / Approach:
The only case that yields a LOW output for an OR gate is when all inputs are LOW simultaneously. Every other combination produces a HIGH output.

Step-by-Step Solution:
Total combinations = 8.LOW output cases = exactly 1 (000).HIGH output cases = 8 − 1 = 7.

Verification / Alternative check:
Enumerate: 001, 010, 011, 100, 101, 110, 111 → all yield HIGH, confirming seven HIGH outputs.

Why Other Options Are Wrong:
1 or 2: underestimate the number of HIGH cases.8: includes the all-zero case, which produces LOW for an OR.

Common Pitfalls:
Forgetting the all-zero case or confusing OR with NOR or AND behavior.

Final Answer:
7