Which letter-cluster will replace the question mark (?) to complete the given series?
ZYXW, STUV, RQPO, ?, JIHG, CDEF
Letter Series Pattern Deconstruction
The series consists of 4-letter blocks: ZYXW, STUV, RQPO, ?, JIHG, CDEF. We need to identify the pattern governing these blocks.
Identify Block Patterns
The blocks follow alternating internal patterns:
- Descending: Letters decrease alphabetically (e.g., ZYXW).
- Ascending: Letters increase alphabetically (e.g., STUV).
The series alternates: Descending (ZYXW), Ascending (STUV), Descending (RQPO), ? (Ascending), Descending (JIHG), Ascending (CDEF).
Analyze First Letter Sequence Differences
Consider the first letter of each block and its alphabetical position (A=1, Z=26):
| Block | First Letter | Position |
| ZYXW | Z | 26 |
| STUV | S | 19 |
| RQPO | R | 18 |
| ? | ? | ? |
| JIHG | J | 10 |
| CDEF | C | 3 |
The differences between consecutive starting letter positions are:
- 26 -> 19: -7
- 19 -> 18: -1
- 18 -> ?: ?
- ? -> 10: ?
- 10 -> 3: -7
This reveals a repeating difference pattern: -7, -1.
Determine Missing Ascending Block
Based on the pattern -7, -1, the next difference after 18 should be -7:
- Starting position of ? = 18 + (-7) = 11
The 11th letter is K. The missing block must start with K.
As established, this position requires an ascending block. The ascending sequence starting with K is KLMN.
Verify KLMN Replacement in Series
The complete series: ZYXW, STUV, RQPO, KLMN, JIHG, CDEF.
- Internal patterns: Descending, Ascending, Descending, Ascending, Descending, Ascending. (Matches)
- First letter sequence: Z(26), S(19), R(18), K(11), J(10), C(3).
- Differences: -7, -1, -7, -1, -7. (Matches)
The cluster KLMN correctly completes the series.
Important Questions from Alphabet Series
A series is given with some letters missing. Choose the correct alternative from the given ones that will complete the series:
BR __ __ NB __ O __ NBA series is given with some letters missing. Choose the set of letters which when sequentially placed shall complete it .
a __ __ dba __ __ bcad __ __ da __ __ cdIn the following letter series, some of the letters are missing which are given in that order as one of the alternatives below It. Choose the correct alternative
_ a _ b _ abaa _ bab _ abbSelect the combination of letters that when sequentially placed in the blanks of the given series will complete the series.
Q _ P _ M _ A _ T _ Q A _ T M
In the series _b_a_ba_b_abab_aab;
fill in the six blanks ( _ ) using one of the following given four choices such that the series follows a specific order.
