Logical Reasoning for PA/SA Exam 2014 : Number Series

1.	Look at this series: 21, 9, 21, 11, 21, 13, 21, ... What number should come next?
	A. 14 B. 15 C. 21 D. 23 Answer & Explanation Answer: Option B Explanation: In this alternating repetition series, the random number 21 is interpolated every other number into an otherwise simple addition series that increases by 2, beginning with the number 9.

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2.	Look at this series: 58, 52, 46, 40, 34, ... What number should come next?
	A. 26 B. 28 C. 30 D. 32 Answer & Explanation Answer: Option B Explanation: This is a simple subtraction series. Each number is 6 less than the previous number.

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3.	Look at this series: 3, 4, 7, 8, 11, 12, ... What number should come next?
	A. 7 B. 10 C. 14 D. 15 Answer & Explanation Answer: Option D Explanation: This alternating addition series begins with 3; then 1 is added to give 4; then 3 is added to give 7; then 1 is added, and so on.

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4.	Look at this series: 8, 22, 8, 28, 8, ... What number should come next?
	A. 9 B. 29 C. 32 D. 34 Answer & Explanation Answer: Option D Explanation: This is a simple addition series with a random number, 8, interpolated as every other number. In the series, 6 is added to each number except 8, to arrive at the next number.

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5.	Look at this series: 31, 29, 24, 22, 17, ... What number should come next?
	A. 15 B. 14 C. 13 D. 12 Answer & Explanation Answer: Option A Explanation: This is a simple alternating subtraction series, which subtracts 2, then 5.