JEMAT cheat sheet

Percentage change: successive changes of a% then b% give a net change of a + b + (ab/100) percent; a 20% rise then 20% fall leaves a net 4% loss.

Simple interest SI = PRT/100; compound interest CI = P(1 + R/100)^T − P. For 2 years, CI − SI = P(R/100)^2.

Profit and loss are computed on cost price unless stated otherwise; selling price = CP × (100 + profit%)/100. Discount is computed on marked price.

Speed–time: distance = speed × time. For a train of length L crossing a platform of length P at speed S, time = (L + P)/S; convert km/h to m/s by multiplying by 5/18.

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

Time and work: if A alone takes a days and B alone b days, together they take ab/(a + b) days. Work rates add; using LCM of days as total work units avoids fractions.

Averages: new average after adding a value x to n items with average A is (nA + x)/(n + 1). For consecutive numbers, average equals the middle term.

Permutations nPr = n!/(n − r)!; combinations nCr = n!/[r!(n − r)!]. nCr = nC(n − r), and nC0 = nCn = 1.

Mensuration: circle area πr², circumference 2πr; cylinder volume πr²h and curved surface 2πrh; sphere volume (4/3)πr³, surface 4πr².

Number series: check successive differences first, then ratios, then squares/cubes or alternating two-series patterns before assuming a random rule.

Coding–decoding: map each letter to its alphabet position (A = 1 … Z = 26); shifts are usually constant, +1 progressive, or reversal of the alphabet.

Blood relations: draw a family tree with gender-marked nodes; vertical lines are parent–child, horizontal lines are siblings or spouses. Never assume gender from a name.

Direction sense: fix north upward and track net displacement with vectors; final distance = √(x² + y²) when the path turns at right angles.

Syllogism: in classical (Aristotelian) treatment, a conclusion follows only if true in every possible diagram of the premises; 'some A are B' does not imply 'some B are A' fails only for 'no' statements.

Seating arrangement: for a circle, fix one person to break rotational symmetry; 'facing centre' means left is clockwise, 'facing outward' reverses left and right.

Analogy and classification: identify the relation type - part-to-whole, cause–effect, worker–tool, synonym/antonym - then apply the same relation to the options.

Clock problems: angle between hands = |30H − 5.5M| degrees; hands coincide 11 times in 12 hours and are opposite 11 times in 12 hours.

Calendar: a normal year shifts the weekday by 1, a leap year by 2; century years are leap only if divisible by 400.

Subject–verb agreement: a singular subject takes a singular verb; with 'either … or' or 'neither … nor', the verb agrees with the nearer subject.

Articles: 'a' before consonant sounds, 'an' before vowel sounds (an hour, a university); 'the' for unique or already-specified nouns.

Prepositions of time: 'in' for months, years and long periods; 'on' for days and dates; 'at' for clock times and festivals.

Tenses: present perfect (has/have + past participle) links past action to present; past perfect (had + participle) marks the earlier of two past actions.

Active to passive: object becomes subject, verb becomes be + past participle, and the original subject moves to 'by …' or is dropped.

Direct to indirect speech: shift present to past, change pronouns to third person, and convert 'now' to 'then', 'today' to 'that day', 'tomorrow' to 'the next day'.

Common error traps: 'one of the' takes a plural noun and singular verb; 'each', 'every', 'either' are singular; 'much' modifies uncountable, 'many' countable nouns.

Reading comprehension: the answer must be supported by the passage, not by outside knowledge; main-idea questions favour the option covering the whole passage, not one detail.

Idioms to know: 'to bite the bullet' (face something painful), 'to let the cat out of the bag' (reveal a secret), 'a blessing in disguise' (apparent misfortune that turns good).

GST in India is a destination-based indirect tax launched on 1 July 2017; it subsumed excise, service tax and VAT, and is levied as CGST, SGST and IGST.

Fundamental business forms: sole proprietorship (unlimited liability), partnership (Indian Partnership Act 1932), LLP (LLP Act 2008, limited liability), and company (Companies Act 2013, separate legal entity).

The four Ps of the marketing mix are Product, Price, Place and Promotion; services add People, Process and Physical evidence (7 Ps).

Break-even quantity = fixed costs ÷ (price per unit − variable cost per unit); above this output the firm makes profit.

Ratio analysis: current ratio = current assets/current liabilities (a rough benchmark is 2:1); debt–equity ratio measures leverage; net profit margin = net profit/sales.

Leadership styles: autocratic (leader decides), democratic (group consults), laissez-faire (group decides). Maslow's hierarchy runs physiological, safety, social, esteem, self-actualisation.

Indian institutions: RBI (central bank, founded 1935, nationalised 1949), SEBI (market regulator, 1992), NABARD (agriculture and rural development, 1982).

Economic terms: GDP is the value of final goods and services produced domestically in a year; inflation is a sustained rise in the general price level, measured in India by CPI and WPI.

Business abbreviations: IPO (first public share sale), FDI (foreign direct investment), MSME (micro, small and medium enterprises), CSR (corporate social responsibility under Section 135 of the Companies Act).