C:
printf("%10.2f", x);

C++:
cout << setw(10) << setprecision(2) << showpoint << x;

Java:
java.text.NumberFormat formatter = java.text.NumberFormat.getNumberInstance();
formatter.setMinimumFractionDigits(2);
formatter.setMaximumFractionDigits(2);
String s = formatter.format(x);
for (int i = s.length(); i < 10; i++) System.out.print(’ ‘);
System.out.print(s);