Comprehension

In a code, the \(r^{\text{th}}\) letter is shifted to the \((27-2r)^{\text{th}}\) letter for \(r = 1, 2, \ldots, 13\). The fourteenth letter is shifted to the \(26^{\text{th}}\) letter, and for \(r = 15, 16, \ldots, 26\), the \(r^{\text{th}}\) letter is shifted to the \((2r-28)^{\text{th}}\) letter. For decoding, the inverse process of the above is followed. Using this coding and decoding, answer the question:

Question: 1

In a certain code, 15789 is written as XTZAL and 2346 is written as NPSU. How is 23549 written in that code?

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List each digit and its corresponding letter side-by-side to ensure you don't mix up digits from different source strings.
Updated On: Jul 3, 2026
  • NPTUL
  • PNTXL
  • NPTSL
  • NBTSL
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The Correct Option is C

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Question: 2

In a code, the $r^{th}$ letter is shifted to $(27-2r)^{th}$ letter for $r=1,2...13$. The fourteenth letter is shifted to $26^{th}$ letter and, for $r=15,16...26$, the $r^{th}$ letter is shifted to $(2r-28)^{th}$ letter. Which letter is coded as Y?

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When decoding, plug the target position into the provided formulas to see which one yields a valid $r$ value.
Updated On: Jul 3, 2026
  • A
  • N
  • B
  • M
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The Correct Option is A

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Question: 3

In a code, the $r^{th}$ letter is shifted to $(27-2r)^{th}$ letter for $r=1,2...13$. The fourteenth letter is shifted to $26^{th}$ letter and, for $r=15,16...26$, the $r^{th}$ letter is shifted to $(2r-28)^{th}$ letter. What is the code letter for P?

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P is past the middle of the alphabet (M=13, N=14), so always use the second formula for letters P through Z.
Updated On: Jul 3, 2026
  • J
  • D
  • L
  • W
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The Correct Option is B

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Question: 4

In a code, the $r^{th}$ letter is shifted to $(27-2r)^{th}$ letter for $r=1,2...13$. The fourteenth letter is shifted to $26^{th}$ letter and, for $r=15,16...26$, the $r^{th}$ letter is shifted to $(2r-28)^{th}$ letter. What is the code word for POTA?

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Since you already found P=D and A=Y in previous questions, you only need to calculate the codes for O and T.
Updated On: Jul 3, 2026
  • DLBY
  • DBYJ
  • DBLY
  • DLYB
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The Correct Option is C

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Question: 5

In a code, the $r^{th}$ letter is shifted to $(27-2r)^{th}$ letter for $r=1,2...13$. The fourteenth letter is shifted to $26^{th}$ letter and, for $r=15,16...26$, the $r^{th}$ letter is shifted to $(2r-28)^{th}$ letter. Which word is decoded as WMCL?

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If multiple formulas are available, try the first range ($r \le 13$) first, as it covers most common word letters like B, E, L.
Updated On: Jul 3, 2026
  • BELL
  • BELT
  • BOLT
  • BOLD
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The Correct Option is B

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