Find the missing number in the series: 7, 10, 8, 11, 9, 12, ...

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A 7
B 12
C 10
D 13

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Answer: C. 10

• Answer: (C) 10
• Explanation: This is an alternating addition and subtraction series. First, 3 is added (7 + 3 = 10), then 2 is subtracted (10 - 2 = 8), then 3 is added (8 + 3 = 11), and so on. Following 12 - 2, the next number is 10.

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Find the missing number in the series: 7, 10, 8, 11, 9, 12, ...

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