Difficulty: Medium
Correct Answer: ÷ x - =
Explanation:
Introduction / Context:
We must choose a sequence of four symbols that, when inserted between the five numbers (9, 3, 3, 3, 6), yields a true equation under standard arithmetic precedence. These puzzles test careful operator placement and precedence awareness.
Given Data / Assumptions:
Concept / Approach:
Interpret each option literally as the four replacements in order. For example, '÷ x - =' gives 9 ÷ 3 × 3 − 3 = 6. Evaluate with precedence (first ÷ and ×), then addition/subtraction, and finally compare both sides.
Step-by-Step Solution:
Using option '÷ x - =': compute left side.9 ÷ 3 = 3; 3 × 3 = 9; 9 − 3 = 6.Thus 6 = 6, the statement is true.
Verification / Alternative check:
Briefly test another option to confirm it fails. For instance, 'x + - =': 9 × 3 + 3 − 3 = 27 + 3 − 3 = 27 ≠ 6.
Why Other Options Are Wrong:
Common Pitfalls:
Overriding precedence (e.g., doing addition before multiplication) or reading the symbols out of order. Always apply the operators exactly where the asterisks are, in the given order.
Final Answer:
÷ x - =
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