Decode operator meanings and evaluate: Mapping: “-” means “×”, “x” means “+”, “+” means “÷”, “÷” means “−”. Evaluate: 40 x 12 + 3 - 6 ÷ 60

Difficulty: Easy

Correct Answer: 4

Explanation:


Introduction / Context:
This is a direct operator-mapping exercise. Replace each printed symbol by its assigned meaning, then compute with standard precedence (× and ÷ first, then + and −), left-to-right within each tier.


Given Data / Assumptions:

  • “-” → ×, “x” → +, “+” → ÷, “÷” → −
  • Expression: 40 x 12 + 3 - 6 ÷ 60
  • Use standard precedence rigorously.


Concept / Approach:
Translate first, then evaluate. Do not mix old and new meanings during arithmetic.


Step-by-Step Solution:
Translate → 40 + 12 ÷ 3 × 6 − 60 Compute ×/÷ left→right: 12 ÷ 3 = 4; then 4 × 6 = 24 Now +/−: 40 + 24 − 60 = 4


Verification / Alternative check:
Parenthesized view: 40 + ((12 ÷ 3) × 6) − 60 = 40 + (4 × 6) − 60 = 40 + 24 − 60 = 4.


Why Other Options Are Wrong:
They arise from swapping the mapping or from evaluating +/− before finishing ×/÷.


Common Pitfalls:
Treating the printed symbols as usual arithmetic signs instead of mapping first; reversing the left-to-right order in chained ×/÷.


Final Answer:
4

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