Difficulty: Medium
Correct Answer: - to +, 2 and 6
Explanation:
Introduction / Context:
This item asks which single operator change combined with swapping a specific pair of numbers will turn a false statement into a true equality. Such tasks test controlled manipulation of arithmetic structure while respecting normal precedence.
Given Data / Assumptions:
Concept / Approach:
Apply the proposed operator change and digit swap to the LHS, then evaluate with standard precedence. Compare the result with 14. Repeat for each option until a match is found.
Step-by-Step Solution:
Option B: change “−” to “+” and swap 2 and 6.First change: 4 × 6 + 2.After swapping 2 ↔ 6 throughout the LHS: 4 × 2 + 6.Evaluate: 4 × 2 = 8; 8 + 6 = 14 ⇒ equality holds.
Verification / Alternative check:
Test a counter-option quickly: Option A yields 2 ÷ 6 − 4 (after its swap), which is ≈ −3.667, not 14. Other options similarly fail.
Why Other Options Are Wrong:
They either collapse the product too much or introduce a division that drives the value away from 14.
Common Pitfalls:
Not applying both operations (operator change + digit swap) or forgetting normal precedence.
Final Answer:
- to +, 2 and 6 produces a true equality.
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