Difficulty: Easy
Correct Answer: (6 : 13 : 20)
Explanation:
Introduction / Context:The triple 23 : 30 : 37 increases by a constant difference: +7, then +7. We must select the option with the same constant-difference pattern.
Given Data / Assumptions:
Concept / Approach:Check each option for B - A = 7 and C - B = 7.
Step-by-Step Solution:
(6 : 13 : 20) → +7, +7 ✓(7 : 15 : 22) → +8, +7 ✗(21 : 28 : 34) → +7, +6 ✗(12 : 19 : 25) → +7, +6 ✗(10 : 18 : 25) → +8, +7 ✗Verification / Alternative check:Only the first option maintains constant +7 increments across both gaps.
Why Other Options Are Wrong:They break the constant-difference requirement.
Common Pitfalls:Stopping after checking the first gap; both gaps must match.
Final Answer:(6 : 13 : 20)
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