Look at this series: 8, 43, 11, 41, __, 39, 17, ... What number should fill in the blank?

• A. 44
• B. 8
• C. 43
• D. 14

Answer: (D)

This is a simple alternating addition and subtraction series. The first series begins with 8 and adds 3; the second begins with 43 and subtracts 2.