Difficulty: Easy
Correct Answer: 5
Explanation:
Introduction / Context:In operator re-mapping questions, symbols are reassigned new meanings. You must first translate the expression into its true operations and then evaluate with standard operator precedence (× and ÷ before + and −). Careful symbol-by-symbol substitution prevents common mistakes.
Given Data / Assumptions:
Concept / Approach:Translate each symbol first, then compute. Do not mix the original symbols with their new meanings during evaluation; complete translation ensures correct precedence and arithmetic.
Step-by-Step Solution:
Translate: "×" → "÷", "÷" → "+", "+" → "−", "−" → "×".So the expression becomes: 16 ÷ 2 + 25 − 7 × 4.Evaluate: 16 ÷ 2 = 8; 7 × 4 = 28; then 8 + 25 − 28 = 5.Verification / Alternative check:Re-translate in a second pass to confirm no symbol was missed; recompute to confirm 5.
Why Other Options Are Wrong:
104, 22, and 4 result from misreading precedence or applying the mapping incorrectly (e.g., translating commas of operations inconsistently).Common Pitfalls:Attempting to compute while translating on the fly; always finish translation first, then apply normal precedence.
Final Answer:5
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