Difficulty: Easy
Correct Answer: 110
Explanation:
Introduction / Context:Binary subtraction mirrors decimal subtraction but with base 2. Recognizing basic patterns such as subtracting 1 from a number simplifies mental computation and checking of results.
Given Data / Assumptions:
Concept / Approach:Since 111₂ is all ones, subtracting 001₂ simply clears the LSB and leaves the higher bits unchanged, equivalent to 7 − 1 = 6 decimal. Convert back to binary after subtraction to confirm.
Step-by-Step Solution:
1) Convert: 111₂ → 7₁₀, 001₂ → 1₁₀.2) Subtract in decimal: 7 − 1 = 6.3) Convert 6 to binary: 6 = 4 + 2 = 2^2 + 2^1 → 110₂.4) Therefore, 111₂ − 001₂ = 110₂.Verification / Alternative check:Perform column-wise binary subtraction: from right to left, 1−1=0; next bits 1−0=1; next 1−0=1 → 110.
Why Other Options Are Wrong:
Common Pitfalls:Attempting unnecessary borrows when subtracting 1 from an odd number ending in 1.
Final Answer:110
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