Base conversion — convert the binary number to decimal. Task: Evaluate the decimal value of binary 1110₂ using positional weights.
Electronics
Number Systems and Codes
Difficulty: Easy
Choose an option
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A3
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B1
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C7
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D14
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E12
Answer
Correct Answer: 14
Explanation
Introduction / Context:Binary-to-decimal conversion reinforces understanding of bit weights (1, 2, 4, 8, …). This is essential when reading register dumps, flags, and immediate constants in low-level code.
Given Data / Assumptions:
- Binary number: 1110₂
- No sign bit or fraction; simple unsigned conversion
Concept / Approach:Sum the weights corresponding to the 1 bits. For 4-bit numbers, the weights from most to least significant are 8, 4, 2, 1.
Step-by-Step Solution:
Pattern: 1 1 1 0Weights: 8 + 4 + 2 + 0Sum: 8 + 4 + 2 = 14Verification / Alternative check:Using polynomial expansion: 12^3 + 12^2 + 12^1 + 02^0 = 8 + 4 + 2 + 0 = 14. Converting 14 back to binary gives 1110₂, confirming the round-trip.
Why Other Options Are Wrong:
- 3, 1, 7, 12: each omits one or more active bit weights.
Common Pitfalls:
- Reading bits right-to-left and misassigning weights (e.g., adding the 1′s place when it is 0).
Final Answer:14