0.30000000000000004
Just adding 0.1 to 0.2 in the language of your choice can be misleading because printing the number might just cut off the digits at some point.Here's an example using perl5:perl -e 'print 0.1+0.2' yields '0.3', which looks OK, howeverperl -e 'print 0.1+0.2-0.3' reveals '5.55111512312578e-17'So, it's better to print the result of 0.1+0.2-0.3For what its worth, perl6 passes this test with flying colours.