Choose the modification that makes the equation true by changing one operator and interchanging two numbers: starting from 4 × 6 − 2 = 14

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:

  • Initial statement: 4 × 6 − 2 = 14 (false, since 4 × 6 − 2 = 24 − 2 = 22).
  • Each option specifies (i) which operator to change into another, and (ii) which two numerals to interchange globally in the left-hand expression.
  • Only one option should make the equation correct.


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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