In a certain code language COMPUTER is written as RFUVQNPC. How will MEDICINE be written in that code language ?

Question

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Correct — D, EOJDJEFM. Crack the rule on the worked example before you touch the answer word. COMPUTER is C-O-M-P-U-T-E-R and its code is R-F-U-V-Q-N-P-C. The first clue is that the code begins with R and ends with C, while the plain word begins with C and ends with R: the string has been reversed. The second clue is what happened to the letters in between. Write COMPUTER, leave the first letter C and the last letter R untouched, and advance each of the six interior letters by one place in the alphabet — O→P, M→N, P→Q, U→V, T→U, E→F. That gives C-P-N-Q-V-U-F-R. Now reverse the whole string: R-F-U-V-Q-N-P-C, which is the given code exactly, letter for letter. The rule is therefore: keep the first and last letters as they are, shift every interior letter one step forward, then reverse. Apply it to MEDICINE, which is M-E-D-I-C-I-N-E. Keep M and the final E; advance the six interior letters E→F, D→E, I→J, C→D, I→J, N→O. That gives M-F-E-J-D-J-O-E. Reverse it: E-O-J-D-J-E-F-M — EOJDJEFM, option (d). Because both steps were verified against the example before being applied, this is a derivation rather than a guess, and there is no ambiguity left to resolve.

Why the other options are wrong — (a) It still begins with M, so the reversal step has not been carried out at all — and the interior letters do not follow the +1 shift either. It is a pure decoy that resembles a coded string without obeying any rule the example supports.  (b) Also begins with M, the first letter of the plain word, which is the tell-tale sign of the commonest error on this question type: solving the substitution correctly and then forgetting that the example was reversed. Check the first and last letters of the given code against the plain word before anything else and this option disappears.  (c) The dangerous one. Its first four letters, EOJD, match the correct answer exactly, so a candidate who works the front of the word and then reads off the option in a hurry will take it. The last four differ — EJEM against the correct JEFM — because the shift has been misapplied to the middle letters. Always finish the string before matching.

Concept: Coding-decoding questions supply a worked example and ask you to reverse-engineer the transformation, so the marks sit in the diagnosis, not the arithmetic. There are only a handful of transformation families and almost every question is a combination of two of them: positional shift (each letter moves a fixed number of places, as in a Caesar cipher), reversal (of the whole word, of pairs, or of alphabet position so that A↔Z, B↔Y and every pair sums to 27), substitution by symbol or number, and position-dependent rules where odd and even places behave differently. The efficient method is to compare the plain word and the code letter by letter and write the gap under each pair. A constant gap means a shift; a gap that alternates in sign means a paired rule; a code whose first letter matches the plain word's last letter means a reversal is in play. Two mechanical aids save time: the EJOTY mnemonic fixes E=5, J=10, O=15, T=20, Y=25 so you can find any letter's position in a second, and remembering that a letter and its mirror image sum to 27 handles the whole reverse-alphabet family.

State PCS 2024 Q99 — Science & Technology PYQ with Answer

State PCS 2024 Q99 — Science & Technology PYQ with Answer