Indian Navy Tradesman Mate cheat sheet

Letter positions: A=1 to Z=26; reverse position = 27 − forward position (A↔Z, M↔N). Opposite-letter pairs are 13 apart in value and 25 apart in index sum.

Alphabet series rule: convert letters to numbers, find the constant difference or pattern (skip 1, skip 2, alternating), then convert back to letters.

Odd-one-out test: check the letter/number relation of each option against the others; the option that breaks the common relation (e.g., sum of positions, vowel pattern) is the answer.

Coding-decoding: for shift codes, find the difference between corresponding letters of the word and its code; a constant shift means +n or −n for every letter.

Blood relations: draw a family tree with symbols - square for male, circle for female, horizontal line for siblings, vertical line for parent-child, double line for spouse.

Direction sense: draw north-up axes; right turn = +90° clockwise, left turn = −90° clockwise. Net displacement = √(x² + y²) for perpendicular moves.

Number series: test differences first, then ratios, then squares/cubes ± constant, then alternating two-series patterns.

Analogy: identify the exact relation (part-whole, worker-workplace, cause-effect, synonym, antonym) before choosing the matching pair.

Ranking: if a person is nth from the left and mth from the right in a row, total persons = n + m − 1.

Average = sum of items ÷ number of items; new average after adding a value x = (old sum + x) ÷ (old count + 1).

Percentage change = (new − old) ÷ old × 100. Successive changes of a% and b% give a net change of a + b + ab/100 percent.

Simple interest = P × R × T ÷ 100. Compound interest = P(1 + R/100)^T − P; for 2 years, CI − SI = P(R/100)².

Profit or loss percent is always calculated on cost price: Profit% = (SP − CP) ÷ CP × 100. If SP is same and profit% = loss%, there is always a net loss of (x/10)² percent.

Speed = distance ÷ time. To convert km/h to m/s multiply by 5/18; to convert m/s to km/h multiply by 18/5.

Boats: downstream speed = boat + stream, upstream speed = boat − stream; boat speed = (down + up) ÷ 2, stream speed = (down − up) ÷ 2.

Time and work: if A alone takes a days and B alone takes b days, together they take ab ÷ (a + b) days.

Ratio and proportion: if a : b = c : d then ad = bc. To divide amount N in ratio a : b : c, shares are N × a/(a+b+c), etc.

Mensuration: area of circle = πr², circumference = 2πr; area of triangle = ½ × base × height; volume of cylinder = πr²h; volume of cube = a³.

Articles: 'a' before consonant sounds, 'an' before vowel sounds (an hour, a university); 'the' for specific or unique items.

Subject-verb agreement: singular subject takes singular verb; words like 'each', 'every', 'either', 'neither' take a singular verb.

Tenses: simple present for habits/facts, present continuous for ongoing actions, present perfect for past action with present relevance (has/have + past participle).

Active to passive: object becomes subject, verb becomes be + past participle, subject becomes 'by + agent' (e.g., 'He wrote a letter' → 'A letter was written by him').

Direct to indirect speech: change pronouns to match the reporter, shift tense one step back (present → past), and change time words (today → that day, tomorrow → the next day).

Synonyms and antonyms: learn word families in pairs, e.g., 'abundant' ↔ 'scarce', 'candid' ↔ 'guarded', 'frugal' ↔ 'extravagant'.

Idioms: 'at the drop of a hat' = immediately; 'once in a blue moon' = very rarely; 'to bite the bullet' = to endure pain bravely; 'a piece of cake' = very easy.

One-word substitutions: 'philanthropist' = lover of mankind; 'misanthrope' = hater of mankind; 'omnipotent' = all-powerful; 'ephemeral' = short-lived.

Spelling rule: 'i' before 'e' except after 'c' (receive, believe); drop final 'e' before a vowel suffix (make → making).

Indian Navy ranks (ascending): Sub Lieutenant → Lieutenant → Lieutenant Commander → Commander → Captain → Commodore → Rear Admiral → Vice Admiral → Admiral. The Admiral rank is held by the Chief of the Naval Staff.

Indian Navy Day is 4 December, commemorating Operation Trident (1971 Indo-Pak war). Navy motto: 'Sham No Varunah' (May the Lord of the Waters be auspicious to us).

Indian Navy commands: Western (Mumbai), Eastern (Visakhapatnam), Southern (Kochi), and training command at Kochi. Andaman and Nicobar Command (Port Blair) is a tri-service command.

Indian Constitution: adopted 26 November 1949, came into force 26 January 1950. Fundamental Rights in Part III (Articles 12–35); Fundamental Duties in Part IVA (Article 51A).

Indian defence ranks: Army - Sepoy to Field Marshal; Air Force - Aircraftsman to Marshal of the Air Force. Highest peacetime gallantry award: Param Vir Chakra (Army), Maha Vir Chakra (second).

National symbols: national bird - Indian peafowl; national animal - Bengal tiger; national flower - lotus; national fruit - mango; national river - Ganga.

Important dates: Republic Day 26 January, Independence Day 15 August, Navy Day 4 December, Army Day 15 January, Air Force Day 8 October, Kargil Vijay Diwas 26 July.

Geography facts: longest river in India - Ganga; highest peak - Kangchenjunga (in India); Tropic of Cancer passes through 8 Indian states; Deccan Plateau lies between Western and Eastern Ghats.

Science basics: SI unit of force - newton; of power - watt; speed of light ≈ 3 × 10⁸ m/s; chemical symbol of sodium - Na, potassium - K, iron - Fe; water boils at 100 °C at sea level.