Logical Reasoning: Letter and symbol series (Online test)

This is a simple subtraction series. Each number is 6 less than the previous number.

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.

This is an alternating addition and subtraction series. In the first pattern, 10 is subtracted from each number to arrive at the next. In the second, 5 is added to each number to arrive at the next.

Explanation:

This is a simple division series; each number is one-half of the previous number.

In other terms to say, the number is divided by 2 successively to get the next result.

4/2 = 22/2 = 11/2 = 1/2(1/2)/2 = 1/4(1/4)/2 = 1/8 and so on.

Explanation:

This is an alternating multiplication and subtracting series: First, multiply by 2 and then subtract 8.

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.

In this series, each number is repeated, then 13 is subtracted to arrive at the next number.