1 Numbers, operations and common notations

  1.1 The number line

2 Calculation with numbers

  2.1 Addition ( $+$ )

  2.2 Subtraction ( $-$ )

  2.3 The plus or minus sign ( $\pm$ )

  2.4 Multiplication ( $\times$ )

  2.5 Division ( $÷$ ) or ( $∕$ )

  2.6 The reciprocal of a number

  2.7 The modulus notation ( $\left|\right|$ )

  2.8 The factorial symbol (!)

3 Rounding to $n$ decimal places

4 Rounding to $n$ significant figures

  4.1 Arithmetical expressions

  4.2 The BODMAS rule

5 Using symbols

6 Combining numbers together using $+,-,\times ,÷$

  6.1 Addition ( $+$ )

  6.2 Subtraction ( $-$ )

  6.3 Multiplication ( $\times$ )

  6.4 Division ( $÷$ )

  6.5 Algebraic expressions

  6.6 The equals sign ( $=$ )

  6.7 The ‘not equals’ sign ( $⁄=$ )

  6.8 The notation for the change in a variable ( $\delta$ )

  6.9 Sigma (or summation) notation ( $\sum$ )