Difficulty: Medium
Correct Answer: + - x
Explanation:
Introduction / Context:We must select a fixed sequence of three operators to make the equation true. Standard precedence applies.
Given Data / Assumptions:
Concept / Approach:Test reasonable combinations; subtraction and multiplication often help reach small targets like 12.
Step-by-Step Solution:
Option B (+ - ×): 7 + 7 - 2 × 1 = 14 - 2 = 12 → true.Other options do not yield 12 under precedence.Verification / Alternative check:Explicitly compute each alternative; only Option B balances.
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:+ - x
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