Writing in Alphabetical order, which name of the following will appear in the last?

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Correct — B, Mohinder. Alphabetical order is settled position by position from the left: compare the first letters, and only if they are identical move to the second, and so on, the first position at which two names differ deciding the matter outright. Stack the four names one under another and read down the columns rather than across the words. Column 1 gives M, M, M, M for Mahinder, Mohinder, Mohender and Mahendra — identical, so it carries no information at all. Column 2 gives a, o, o, a, and this is the first split: 'a' precedes 'o', so both names beginning Ma- come before both names beginning Mo-, and the name that appears last must be Mohinder or Mohender. Column 3 gives h, h, h, h — again identical and again useless. Column 4 gives i, i, e, e, and this is the second split: within the Mo- pair, Mohender has 'e' and Mohinder has 'i', and since 'e' precedes 'i' in the alphabet, Mohender comes before Mohinder. Mohinder therefore stands last, which is option (b). The full order of all four is Mahendra, Mahinder, Mohender, Mohinder — and note that columns 5 and 6, both n and both d for every name, and columns 7 and 8, which alone would separate Mahendra from the rest, are never consulted, because the decision has already been made at column 4. Two letter positions out of eight decide this entire question.

Why the other options are wrong — (a) Second in the order, and it is the answer of a candidate who sorts on the wrong column. The visually striking difference across the set is '-hinder' against '-hender', so the eye fastens on column 4 and never checks column 2 — but column 2 is the earlier one and therefore the decisive one, and Mahinder's 'a' there puts it ahead of both names beginning Moh-. In lexicographic comparison an earlier position always outranks a later one, exactly as the hundreds digit outranks the units digit in a number.  (c) Third in the order, and the closest wrong answer on the page: it matches Mohinder exactly for M, o and h, so everything turns on column 4, where Mohender has 'e' and Mohinder has 'i'. Since 'e' is the fifth letter of the alphabet and 'i' the ninth, Mohender comes first of the two. This option is picked by candidates who reach column 4 correctly and then reverse its verdict, and by anyone who stops at column 3, where the two Moh- names are still tied and look interchangeable.  (d) First of all four — 'a' at column 2 and 'e' at column 4 — so it is the precise answer to the opposite question. It is also the most visually distinctive of the set, being the only one that ends in a vowel and the only one spelt in the standard Devanagari-to-Roman form of the name, which makes it stand out and feel like the odd, and therefore the extreme, member. The stem asks which name appears in the last, and a candidate who works the order out correctly and then reads off the wrong end of it loses the mark at the final step.

Concept: Alphabetical order, called lexicographic order once it is stated as a rule, is a strict left-to-right comparison and nothing else. To place two strings, compare the characters at position 1; if they are the same, move to position 2; continue until the first position at which they differ, and let the alphabet's own order — a before b before c, up to z — decide. Everything after that first difference is irrelevant, however long the words are. One extra clause completes the rule: if one word matches the other all the way through and then simply runs out, the shorter word comes first, so 'Ram' precedes 'Rama' and 'Since' precedes 'Sincere'. Length otherwise decides nothing, and a longer word is not a later word. This single rule is what builds a dictionary, a telephone directory, a book index, an electoral roll and a merit list arranged by name, and it is the default sort for text in every computer language. The one refinement worth knowing but not applying in an exam: a naive computer sort compares character codes, and in ASCII and Unicode every capital letter sorts before every small letter, so a machine would put 'Zebra' before 'apple'. Exam setters always intend the ordinary dictionary sense, in which case is ignored.

State PCS 2025 Q5 — Science & Technology PYQ with Answer

State PCS 2025 Q5 — Science & Technology PYQ with Answer