Has anyone done a prg/ algorithm to round decimal currency to the nearest 5 ?

Eg if the value is $45.43 and 45.44 then rounded to 45.45
45.41 and 45.42 round to 45.40
45.46 and 45.47 down to 45.45
45.48 and 45.49 upto 45.50

Thanks in advance.

This is a legal requirement for cash transactions in Australia

Bernard