Maths EOY

ratio definition

A comparison of two quantities by division: a : b or a/b

simplify a ratio

Divide both terms by their greatest common factor (GCF)

proportion definition

Two ratios equal: a/b = c/d

a proportion

Set a/b = c/d and cross multiply: a × d = b × c

area of a triangle

½ × base × height

right angled triangle formula (pythagoras' theorum)

a² + b² = c²

mean

sum of the numbers over amount

mode

highest frequency in a data set

median

Middle value when data is ordered (or average of middle two)

range

Max − Min

a linear sequence

a sequence where it goes up the same amount each time

equation of a straight line

mx + c (m = gradient, c = y-intercept)

percentage increase

[(New − Original) ÷ Original] × 100%

integer

Any whole number:

a factor

two number divided by eachother

a multiple

product of two numbers

area of a rectangle

length × width

volume of a cylinder

πr²h

circumference of a circle

2πr

area of a circle

πr²

cuboid surface area

2(lw + lh + wh)

gradient

(y₂ − y₁) / (x₂ − x₁)

Formula for the area of a rectangle

A = l × w

Formula for the area of a parallelogram

A = base × height

Formula for the area of a trapezium

A = ½ × (a + b) × height