Fill in the blank with the correct number in this number series: 5, 15, 7, 12, __, 9, 11,... ?	Choose the correct choice.
A) 6 B) 9 C) 8 D) 7 E) 5
In this simple alternating subtraction and addition series; The first series begins with 5 and adds 2; the second begins with 15 and subtracts 3, and so on.   Answer: 9
<result>B</result>
Fill in the blank with the correct number in this number series: 5, 15, 7, 12, __, 9, 11,... ?