You can use a decimal point to show which digits are whole numbers and which are decimal fractions ... to move is by looking at the zeros in 10, 100 and 1000. There are 3 zeros in 1000, so ...

40 ÷ 1000 = 0.04 Dividing decimals by 10, 100 or 1000 is useful in everyday life. It can be used to convert measures, such as centimetres to metres, grams to kilograms and millilitres to litres.