# Mathematics

HideShow resource information
• Created by: Emma Gent
• Created on: 08-05-13 18:16

## Inverse Operations

INVERSE - the word 'inverse' means opposite

The inverse of adding is subtracting

The inverse of subtracting is adding

The inverse of multiplying is dividng

The inverse of dividing is multiplying

1 of 8

## Order of Operations (BIDMAS)

1) Brackets

2) Indices

3) Division

4) Multiplication

6) Subtraction

2 of 8

## Negative Numbers

-10 -8 -6 -4 -2 0

All numbers above 0 are positive numbers

All numbers below 0 are negative numbers

0 is neither positive nor negative.

Two Signs Together - positive and negative

2 x + = positive 2 x - = positive

+ and - = negative

- and + = negative

3 of 8

## Divisibility

1           all whole numbers divide by 1

2           if the number ends in 0,2,4,6 or 8

3           add the digits - will divide by 3

5           ends in 0 or 5

10         ends in 0

4 of 8

## Sequences

Sequences are very important in maths. We can often make sense of puzzles by looking for sequences or patterns.

Each number in a sequence is called a term. The rule that connects the terms is called the term-to-term rule. eg. 4,7,10,13,16... The first term is 4. The term-to-term rule is that we 'add 3'. if you know the first term and the term-to-term rule, you can generate as many teerms as you like.

An ascending sequence is one that goes up. A descending sequence is one which goes down. An infinite sequence is one which goes on for ever. A finite sequence is one which has an end. Terms of a sequence which are next to each other, are called consecutive.

5 of 8

## Algebra + Substitution

ALGEBRA

Remember, algebra is substitung a letter for a number that we dont know yet. We follow the same rules for algebra as we do for numbers. To decide the order in which to do things, we still use BIDMAS. We can use the concept of 'undoing' to rearrange algebra. Sometimes we rearrange algebra even when it doesnt get us to a numerical answer.

SUBSTITUTION

Substitution is where we find out the value of a letter in algebra.

6 of 8

## Area + Perimeter

PERIMETER

When we find the perimeter of a shape, we measure all the way outside. The word 'perimeter' comes from the greek 'peri' which means around, and 'meter' which means 'to measure'.

AREA

The space inside a 2D shape can be measured in cm2, m2, mm2

Calculated using formulae, or occasionally by counting squares.

AREA OF A RECTANGLE = length x width

AREA OF A TRIANGLE = base x height

2                (height must be perpendicular to base)

7 of 8

## Equivalent Fractions

Equivalent fractions are fractions that are the same amount but use differnt numbers. 1/2 = 4/8 = 8/16 = 16/32 etc etc

A pair of equivalent fractions can be found where both the numerators and denominators are multiplied  by the same number.

8 of 8