What is the missing number in this series? 8 2 14 6 11 ? 14 6 18 12
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16
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9
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15
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6
Reveal answer
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B
Correct answer
Explanation
This series follows an interleaved pattern. Odd positions (1st, 3rd, 5th, 7th, 9th): 8, 14, 11, 14, 18 follow the pattern: +6, -3, +3, +4. Even positions (2nd, 4th, 6th, 8th, 10th): 2, 6, ?, 6, 12 follow +4, +3, +3, +6. The missing number is 9, completing both patterns.
AI explanation
Grouping the ten numbers into five consecutive pairs (8,2), (14,6), (11,?), (14,6), (18,12), the middle three pairs all share the same sum of 20: 14+6=20 and, matching that, 11+? =20 requires ?=9. The first pair (sum 10) and last pair (sum 30) bookend that steady middle run, making 9 the value that keeps the pattern consistent.