TS ICET flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Data sufficiency decision rule

Evaluate each statement alone against the question stem without using the other statement. If either alone yields a unique answer, the answer is 'either alone sufficient'; use both only when neither alone works.

Sufficiency for yes/no questions

A yes/no data sufficiency question is answered only when a statement forces a definite yes or a definite no in every valid case. A statement that allows both outcomes is insufficient.

Two equations unique solution

Two linear equations in x and y have a unique solution only when the coefficient ratios of x and y differ. Equal ratios mean parallel or identical lines, giving no solution or infinitely many.

Clock hand angle formula

The angle between the hour and minute hands at h hours and m minutes is the absolute value of 30h − 5.5m degrees. If it exceeds 180, subtract it from 360 to get the smaller angle.

Calendar odd days

Odd days are the remainder when total days are divided by seven. A normal year has 1 odd day, a leap year 2, and 400 consecutive years have 0, so the calendar repeats every 400 years.

Painted cube counts

A cube cut into n³ unit cubes yields 8 cubes with three painted faces, 12(n−2) with two, 6(n−2)² with one, and (n−2)³ with none painted at all.

Syllogism conversion rules

'All A are B' does not convert to 'All B are A'. 'Some A are B' converts to 'Some B are A'. 'No A is B' converts to 'No B is A' and also implies 'No B is A'.

Successive percentage change

Two successive changes of a percent and b percent produce a net change of a + b + ab/100 percent. A rise then an equal fall always leaves a net loss of r²/100 percent.

Compound interest formula

Amount equals principal times (1 + r/100) raised to n for annual compounding. For half-yearly compounding use rate r/2 over 2n periods; for quarterly use r/4 over 4n periods.

Combined work formula

If A finishes a job in x days and B in y days, working together they take xy/(x + y) days. Using the LCM of x and y as total work units avoids fractions in intermediate steps.

Speed unit conversion

Multiply kilometres per hour by 5/18 to convert to metres per second, and multiply metres per second by 18/5 to return to kilometres per hour. A train crossing a platform adds its own length.

Harmonic mean average speed

For two equal distances covered at speeds a and b, average speed is 2ab/(a + b), the harmonic mean. The arithmetic mean (a + b)/2 overstates it unless a equals b.

Quadratic root relations

For ax² + bx + c = 0, the sum of roots is −b/a and the product is c/a. The discriminant b² − 4ac is positive for distinct real roots, zero for equal roots, negative for imaginary.

Section formula coordinates

A point dividing the join of (x₁, y₁) and (x₂, y₂) internally in ratio m : n has coordinates ((mx₂ + nx₁)/(m + n), (my₂ + ny₁)/(m + n)).

Pythagorean trigonometric identity

For any angle θ, sin²θ + cos²θ = 1. Dividing by cos²θ gives 1 + tan²θ = sec²θ, and dividing by sin²θ gives 1 + cot²θ = cosec²θ.

Cone and sphere mensuration

A cone has volume ⅓πr²h and slant height √(r² + h²). A sphere has volume 4/3 πr³ and surface area 4πr²; a hemisphere's total surface is 3πr².

Mean median mode relation

For moderately skewed data the empirical relation Mode = 3 Median − 2 Mean holds approximately. In a perfectly symmetric distribution all three measures coincide at the same value.

Coefficient of variation

Coefficient of variation equals standard deviation divided by mean, multiplied by 100. It compares variability across datasets with different units or very different means.

Pie chart sector angle

Each sector's central angle equals the component divided by the total, multiplied by 360 degrees. Its percentage share is the component divided by the total times 100.

Standard deviation definition

Standard deviation is the positive square root of variance, where variance is the mean of squared deviations from the mean. Adding a constant to every observation leaves it unchanged.

Idiom: let the cat out

'To let the cat out of the bag' means to reveal a secret carelessly or prematurely. It describes accidental disclosure, not deliberate announcement of good news.

Fewer versus less

Use 'fewer' with countable plural nouns such as fewer students, and 'less' with uncountable nouns such as less water. 'Amount' pairs with uncountable, 'number' with countable.

Neither nor verb agreement

With 'neither … nor' or 'either … or', the verb agrees with the subject nearer to it. 'Neither the manager nor the clerks were present' takes a plural verb.

Dangling modifier error

An introductory participial phrase must describe the subject of the main clause. 'Walking down the road, a tree was seen' is wrong because the tree was not walking.

Main idea versus detail

Main-idea questions ask for the passage's central claim, usually stated in the first or last paragraph. Options quoting a single supporting fact are details, not the main idea.

Inference question rule

An inference must follow logically from the passage without outside knowledge. Options using absolutes like always or never, or facts true generally but absent from the text, are wrong.

Paragraph opening sentence

A paragraph's opening sentence usually makes a general statement and contains no pronoun referring backward. Sentences beginning with 'this' or 'such' normally follow it.

RAM versus ROM

RAM is volatile working memory that loses contents when power is off. ROM is non-volatile and retains firmware instructions. Secondary storage such as SSDs keeps data permanently.

Compiler versus interpreter

A compiler translates the whole source program into machine code before execution. An interpreter translates and executes one statement at a time, which aids debugging but runs slower.

Repo rate meaning

The repo rate is the interest rate at which the central bank lends short-term funds to commercial banks against securities. Raising it typically tightens credit and cools inflation.

Accounting equation

Assets equal liabilities plus owners' equity. Every transaction keeps this balance, which underlies the balance sheet and double-entry bookkeeping.

IPO and market capitalisation

An IPO is a company's first sale of shares to the public. Market capitalisation is the current share price multiplied by the total number of shares outstanding.