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Question

Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.

ACF, GIL, ?, SUX

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is
MOR

Letter Series Pattern Analysis

The question asks us to identify the missing letter cluster in the given series: ACF, GIL, ?, SUX.

Step 1: Identify the Pattern

We need to determine the rule connecting consecutive clusters by examining the alphabetical positions of the letters.

  • Compare the first cluster (ACF) with the second cluster (GIL).
  • A (position 1) $\rightarrow$ G (position 7): The difference is $7 - 1 = 6$.
  • C (position 3) $\rightarrow$ I (position 9): The difference is $9 - 3 = 6$.
  • F (position 6) $\rightarrow$ L (position 12): The difference is $12 - 6 = 6$.

The pattern is a consistent shift of +6 positions in the alphabet for each corresponding letter.

Step 2: Calculate the Missing Cluster

Apply the identified '+6' pattern to the letters of the cluster GIL to find the missing cluster.

  • First letter: G (position 7) + 6 = 13. The 13th letter is M.
  • Second letter: I (position 9) + 6 = 15. The 15th letter is O.
  • Third letter: L (position 12) + 6 = 18. The 18th letter is R.

Based on this calculation, the missing cluster is MOR.

Step 3: Verify the Sequence

To confirm, check if the '+6' pattern applied to MOR results in the final cluster, SUX.

  • M (position 13) + 6 = 19, which is S.
  • O (position 15) + 6 = 21, which is U.
  • R (position 18) + 6 = 24, which is X.

The pattern holds true, confirming that MOR is the correct cluster.

Conclusion

The letter cluster that replaces the question mark (?) is MOR.

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Similar Questions

  1. What should come in place of the question mark (?) in the given series based on the English alphabetical order?

    CHR HMW MRB RWG ?
  2. Select the letter-cluster from among the given options that can replace the question mark (?) in the following series. 

    KL, MO, OR, ?

  3. Select the letter-cluster from among the given options that can replace the question mark (?) in the following series. 

    DW, HS, LO, PK, ?

  4. Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
    ab, fg, jk, mn, ?
  5. Select the letter cluster from among the given options that can replace the question mark (?) in the following series.

    CF, IL, OR, ?
  6. Select the letter from among the given options that can replace the question mark (?) in the following series.

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  7. Select the letter from among the given options that can replace the question mark (?) in the following series.

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  8. Select the letter cluster from among the given options that can replace the question mark (?) in the following series.

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Important Questions from Letter Based Series

  1. Select the option that represents the letters that when placed from left to right in the blanks below will complete the given letter series.

    M N _ O J K M _ Q O J K _ N Q _ J K M N Q O _ K M N

  2. Select the option that represents the letters that when placed from left to right in the blanks below will complete the given letter series. 

    B _ E N B _ C E N B B C _ N B B C E _ B _ C

  3. Select the option that is related to the fifth letter-cluster in the same way as the second letter-cluster is related to the first letter-cluster and the fourth letter-cluster is related to the third letter-cluster.

    MSD: NHW :: OAE : LZV :: NIP : ?

  4. Select the option that represents the letters that when sequentially placed from left to right in the blanks below will complete the letter series.

    Y _ Y _ _ Y _ T _ Y _ Y

  5. Select the option that represents the letters that when sequentially placed from left to right in the blanks below will complete the letter series.

    Y _ Y _ _ Y _ T _ Y _ Y

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