It should be elsif, not elseif.

In fact, when I try running this I get an error telling me this very clearly:

elseif should be elsif at ./test.pl line 18.
syntax error at ./test.pl line 20, near ")
               {"
Execution of ./test.pl aborted due to compilation errors.

There's no need to check that the price is greater than the previous limit since that's already been determined by the previous condition. Also, the '.00' isn't required although it shouldn't hurt and does make it pretty clear that you're dealing with monetary amounts.

if ($total_price < 20.00) {
    $ship_price = 3.50;
} elsif ($total_price < 50.00) {
    $ship_price = 5.50;
} elsif ($total_price < 80.00) {
    $ship_price = 10.50;
} # else free shipping?
[download]

---
print map { my ($m)=1<<hex($_)&11?' ':'';
$m.=substr('AHJPacehklnorstu',hex($_),1) }
split //,'2fde0abe76c36c914586c';
[download]

The syntax is elsif not elseif. You need an else clause otherwise if the cost is >80 you get free (undef probably) shipping.....

for ( my $total_price = 10; $total_price < 100; $total_price += 10 ) {
    if ($total_price < 20.00) {
        $ship_price = 3.50;
    }
    elsif  (($total_price >= 20.00) && ($total_price < 50.00)) {
        $ship_price = 5.50;
    }
    elsif (($total_price >= 50.00) && ($total_price < 80.00))  {
        $ship_price = 10.50;
    }
    else {
         warn "that's expensive!\n";
        $ship_price = 15;
    }
    
    my $grande_costa = $total_price + $ship_price;
    print <<STUFF;
Total price: $total_price
Shipping:    $ship_price
Grand Total: $grande_costa

STUFF

}
[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

No disprespect intended, but skipping the spelling of elsif -v- elseif issue, if you bought books which show indentation done that way, I suggest you take them back and see if you can get your money back.:^)

Thanks. I knew it was something simple and stupid on my part.