According to the series given below, fill in the blank with a suitable letter that would satisfy the series.
\text{Z, A, Y, B, X, C, \_\_\_\_\_\_\_\_}}
- AD
- BW
- CU
- DV
Solution & Step-by-step Explanation
The series is an alternating letter series consisting of two independent interwoven patterns:
First pattern (odd positions): Z, Y, X, ...
Z−1=Y
Y−1=X
Next term in this track (position 7): X−1=W
Second pattern (even positions): A, B, C, ...
A+1=B
B+1=C
Since the blank is at the 7th position, it belongs to the first pattern track.
Therefore, the next letter is X−1=W.
First pattern (odd positions): Z, Y, X, ...
Z−1=Y
Y−1=X
Next term in this track (position 7): X−1=W
Second pattern (even positions): A, B, C, ...
A+1=B
B+1=C
Since the blank is at the 7th position, it belongs to the first pattern track.
Therefore, the next letter is X−1=W.