Select the number from among the given options that can replace the question mark(?) in the following series.
159, 146, ?, 120, 107, 94, 81
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 133
To complete this series, we can observe that each number is decreasing by 13:
159 - 13 = 146
146 - 13 = 133
133 - 13 = 120
120 - 13 = 107
107 - 13 = 94
94 - 13 = 81
So, the missing number in the series is 133.
Hence, the correct answer is 133