Difficulty: Medium
Correct Answer: = ÷ - +
Explanation:
Introduction / Context:These problems test whether you can place arithmetic symbols so that both sides of an equation balance. You must respect standard precedence (× and ÷ before + and −) on each side of the equality, and the single “=” must split the statement into a left-hand side (LHS) and a right-hand side (RHS).
Given Data / Assumptions:
Concept / Approach:Try options that place “=” where the remaining three operators can naturally form a simple calculation. Check each option with clean arithmetic to avoid precedence mistakes.
Step-by-Step Solution:
Test Option C: s1 = “=”, s2 = “÷”, s3 = “−”, s4 = “+”.This yields: 24 = 34 ÷ 2 − 5 + 12.Compute RHS with precedence: 34 ÷ 2 = 17; then 17 − 5 + 12 = 12 + 12 = 24.Hence LHS 24 equals RHS 24 → true.Verification / Alternative check:Briefly test other choices: they evaluate to values different from 24 (e.g., 24 + 34 ÷ 2 × 5 = 109; 24 = 34 ÷ 2 + 5 − 12 gives 10). Thus only Option C balances.
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:= ÷ - +
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