Difficulty: Easy
Correct Answer: 140
Explanation:
Given data
1, 5, 14, 30, 55, 91, ?
Concept/Approach
Examine first differences for a recognizable pattern.
Step-by-step
5 − 1 = 4 = 2² 14 − 5 = 9 = 3² 30 − 14 = 16 = 4² 55 − 30 = 25 = 5² 91 − 55 = 36 = 6² Next difference = 7² = 49 ⇒ 91 + 49 = 140
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