Home > Practice > Verbal Reasoning > Series Completion > Miscellaneous
61. 20, 20, 17, 17, 14, 14, 11, ... choose which pair of numbers comes next?
Solution:
This is a simple subtraction with repetition series. It begins with 20, which is repeated, then 3 is subtracted, resulting in 17, which is repeated, and so on.
62. 61, 57, 50, 61, 43, 36, 61, ... choose which pair of numbers comes next?
Solution:
This is an alternating repetition series, in which a random number, 61, is interpolated as every third number into an otherwise simple subtraction series. Starting with the second number, 57, each number (except 61) is 7 less than the previous number.
63. 9, 12, 11, 14, 13, 16, 15, ... choose which pair of numbers comes next?
Solution:
This is a simple alternating addition and subtraction series. First, 3 is added, then 1 is subtracted, then 3 is added, 1 subtracted, and so on.
64. 4, 8, 22, 12, 16, 22, 20, 24, ... choose which pair of numbers comes next?
Solution:
This is an alternating repetition series, with a random number, 22, interpolated as every third number into an otherwise simple addition series. In the addition series, 4 is added to each number to arrive at the next number.
65. 40, 40, 31, 31, 22, 22, 13, ... choose which pair of numbers comes next?
Solution:
This is a subtraction series with repetition. Each number repeats itself and then decreases by 9.
66. 1, 10, 7, 20, 13, 30, 19, ... choose which pair of numbers comes next?
Solution:
Here, every other number follows a different pattern. In the first series, 6 is added to each number to arrive at the next. In the second series, 10 is added to each number to arrive at the next.
67. 10, 20, 25, 35, 40, 50, 55, ... choose which pair of numbers comes next?
Solution:
This is an alternating addition series, in which 10 is added, then 5, then 10, and so on.
68. 42, 40, 38, 35, 33, 31, 28, ... choose which pair of numbers comes next?
Solution:
This is an alternating subtraction series in which 2 is subtracted twice, then 3 is subtracted once, then 2 is subtracted twice, and so on.
69. 6, 10, 14, 18, 22, 26, 30, ... choose which pair of numbers comes next?
Solution:
This simple addition series adds 4 to each number to arrive at the next.
70. 8, 12, 9, 13, 10, 14, 11, ... choose which pair of numbers comes next?
Solution:
This is an alternating addition and subtraction series, in which the addition of 4 is alternated with the subtraction of 3.