The .. operator steps by one, you can't change that behavior. But you can do it with a for loop:

my @results;
for (my $i=0; $i <= 79; $i++) {
    push @results, ($i/10+1.5);
}
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It seems a bit awkward but it give's you the right result. Please notice that I didn't loop from 1.5 to 9.4 with a stepping of .1 for that would get imprecise (I got with a quick perl -e test 5.99999999999999 instead of 6). You can't go precisely if you are calculating with floats.
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use signature; signature(" So long\nAlfie");