Difficulty: Easy
Correct Answer: = ÷ - +
Explanation:
Introduction / Context:
We must insert four signs, in the listed order, to make a true equation from the five numbers.
Given Data / Assumptions:
Each option provides the four operators for the 1st→4th asterisks.
Concept / Approach:
Test candidates efficiently using precedence (×, ÷ before +, −) and the position of “=” which splits LHS and RHS.
Step-by-Step Solution:
Option (c): 24 = 34 ÷ 2 − 5 + 12.
Compute RHS: 34 ÷ 2 = 17; 17 − 5 + 12 = 12 + 12 = 24. Balanced ⇒ true.
Option (a): 24 + 34 ÷ 2 × 5 = 12 ⇒ 24 + (17 × 5) = 109 ≠ 12.
Option (b): 24 = 34 ÷ 2 + 5 − 12 ⇒ 24 = 10 (false).
Option (d): 24 + 34 ÷ 2 = 5 × 12 ⇒ 24 + 17 = 60 (false).
Verification / Alternative check:
Re-evaluate (c) with precedence to confirm RHS exactly 24.
Why Other Options Are Wrong:
They evaluate to values not equal to the opposite side of “=”.
Common Pitfalls:
Ignoring operator precedence or misplacing the equality in mental parsing.
Final Answer:
= ÷ - +
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