Rounding Mechanism to nearest 0.05

Question

I would like to solve rounding mechanism by using php4,5.2 and below (not 5.3) Currently I am doing 0.05 rounding, something like this page:

http://www.bnm.gov.my/in

Answer 1

//Round to nearest 0.05
echo round ($number * 20, 0) / 20;

//Round Up to nearest 0.05
echo ceil ($number * 20) / 20;

//Round Down to nearest 0.05
echo floor ($number * 20) / 20;