how to display a percentage from a float number ?

Hi !
how to display a percentage from a float number ? Imagine :

Percentage = 12.58585 ' a float number in my program

now i want display :

your percentage : 12.58%
your score 12,58 x 1000 = 12580

other case :

your percentage : 100%
your score 100% x 1000 = 100000

another :

your percentage : 1.58%
your score 1.58 x 1000 = 1580

Thanks for your help !