ISEB Common Pre-Test cheat sheet

Place value: each column is 10 times the one to its right, so multiplying by 10 shifts every digit one column left and appends a zero.

Fractions: to add or subtract, first rewrite over a common denominator; to multiply, multiply numerators and denominators separately; to divide, multiply by the reciprocal.

Percentages: a percentage is a fraction over 100, so 35% = 0.35 = 7/20; increase by 15% means multiply by 1.15, decrease by 15% means multiply by 0.85.

Order of operations: brackets, then indices, then multiplication and division left to right, then addition and subtraction left to right.

Area and perimeter: rectangle area = length x width; triangle area = 1/2 x base x perpendicular height; parallelogram area = base x perpendicular height.

Speed, distance, time: speed = distance / time, distance = speed x time, time = distance / speed; keep units consistent before calculating.

Angles: angles on a straight line total 180 degrees, angles around a point total 360 degrees, and angles in a triangle total 180 degrees.

Ratio: divide the total by the number of parts to find one part, then multiply by the number of parts required; scale factors apply to every dimension.

Averages: mean = total / count; median = middle value when ordered; mode = most frequent value; range = largest minus smallest.

Skimming means reading quickly for the main idea; scanning means hunting for one specific detail such as a date or name.

Inference is a conclusion drawn from clues in the text plus general knowledge; it is never stated word for word.

A fact can be checked and proved; an opinion expresses a viewpoint and often uses evaluative words such as best, boring, or should.

A noun names a person, place, thing, or idea; a pronoun replaces a noun; an adjective modifies a noun; an adverb modifies a verb, adjective, or other adverb.

A main clause contains a subject and a finite verb and can stand alone; a subordinate clause cannot stand alone and is often introduced by because, although, when, or which.

Apostrophes show possession (the dog's bowl, the dogs' bowls) or contraction (don't, it's); its without an apostrophe is possessive, it's means it is.

Commas separate items in a list, mark off extra information, and follow introductory phrases; a comma splice joins two main clauses with only a comma and is an error.

Direct speech uses inverted commas around the exact words, with a comma before the closing inverted comma when a reporting clause follows.

Tone and mood are conveyed through word choice, sentence length, and punctuation; short sentences often create tension or urgency.

Analogies: identify the exact relationship between the first pair (for example part to whole, or worker to tool) and apply the same relationship to the second pair.

Odd one out: test each word against a single rule, such as same word class, same category, or same letter pattern; the word breaking the rule is the answer.

Letter series: convert letters to positions (A=1 to Z=26) and look for constant steps, increasing steps, or alternating sequences.

Alphabetical order: compare words letter by letter from the left; if the first letters match, move to the second, and so on.

Word ladders and hidden words: look for a smaller word inside a longer one, and check whether removing one letter leaves a real word.

Codes: find how each letter shifts between plain and coded word, then apply the same shift; check whether the shift changes direction mid-word.

Synonyms share meaning; antonyms are opposites; homophones sound alike but are spelled differently (their, there, they're).

Compound words join two whole words (sun + flower = sunflower); a prefix goes before the root and a suffix after it.

Classification: group words by shared category, such as animals, occupations, or collective nouns, and reject any word that fits no group.

Rotation turns a shape about a point without changing its size or mirroring it; reflection flips it, so a reflected letter or flag points the opposite way.

Count sides, vertices, and enclosed regions first; many sequences alternate between two counts or increase by a constant step.

Track one element at a time across a series - position, shading, size, orientation - rather than trying to see the whole change at once.

Clockwise and anticlockwise movement is usually by a fixed number of positions, such as one corner or 90 degrees per step.

Shading rules commonly alternate (shaded, unshaded, shaded) or follow the count of sides, so test both before choosing.

In analogy pairs, describe the change from first to second figure precisely, then apply exactly that change to the third figure.

Symmetry: count lines of symmetry and check rotational symmetry; a square has four lines, an equilateral triangle has three, a circle has infinitely many.

Nets: a cube net has six squares and folds so that opposite faces never touch; mentally fold the net rather than guessing.

Layers and overlaps: where shapes overlap, the rule may be that lines cancel out, that shading combines, or that only the outer outline remains.