If “+” means “÷”, “−” means “+”, “×” means “−” and “÷” means “×”, evaluate: 24 ÷ 12 − 18 + 9

Difficulty: Easy

Correct Answer: 290

Explanation:


Introduction / Context:
We replace each printed operator with its new meaning and then evaluate with standard precedence.


Given Data / Assumptions:

  • Mappings: “+”→“÷”, “−”→“+”, “×”→“−”, “÷”→“×”.
  • Expression: 24 ÷ 12 − 18 + 9.


Concept / Approach:
First rewrite the expression with the true operations, then compute using precedence.


Step-by-Step Solution:
24 ÷ 12 becomes 24 × 12 (since ÷→×).“− 18” becomes “+ 18”. “+ 9” becomes “÷ 9”.So value = 24 × 12 + 18 ÷ 9 = 288 + 2 = 290.


Verification / Alternative check:
Checking each option shows only 290 matches the evaluated result.


Why Other Options Are Wrong:
They correspond to arithmetic done before remapping or with wrong precedence.


Common Pitfalls:
Treating the printed operators literally instead of applying the mapping.


Final Answer:
290.

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