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AND gate output evaluation: Given a 3-input AND gate with inputs A = 1, B = 0, C = 1, determine whether the output will be LOW. Assess the statement.

Difficulty: Easy

Correct
Incorrect
Output is HIGH because majority are HIGH
Not enough information is provided

Correct Answer: Correct

Explanation:

Introduction / Context:
Multi-input AND gates implement logical multiplication across all inputs. Only when every input is 1 does the output become 1. A single 0 forces the output to 0, irrespective of the other inputs.

Given Data / Assumptions:

Gate: 3-input AND.
Inputs: A = 1, B = 0, C = 1.
Output labeled as “LOW” corresponds to logic 0.

Concept / Approach:
The expression for the output X is X = ABC. Substitute the given input values and evaluate the product to determine if the output is 0 (LOW) or 1 (HIGH).

Step-by-Step Solution:

Start with X = A * B * C.Substitute: X = 1 * 0 * 1.Compute: 1 * 0 = 0; 0 * 1 = 0 → X = 0 (LOW).

Verification / Alternative check:
Truth rule: If any input of an AND gate is 0, the output must be 0. Here B = 0, so X = 0 despite A and C being 1.

Why Other Options Are Wrong:

Incorrect: Contradicts AND behavior.“Majority are HIGH”: AND does not use majority logic; it requires all HIGH.Not enough information: Gate and inputs fully determine the output.

Common Pitfalls:
Confusing AND with majority or voting logic; assuming two highs outvote one low.

AND gate output evaluation: Given a 3-input AND gate with inputs A = 1, B = 0, C = 1, determine whether the output will be LOW. Assess the statement.

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