tab@music4:~/Pianoforte/Development/Perlmonks 12:19:50 $ cat 11154494.pl 
#!/usr/bin/perl

use strict;
use warnings;

my $str = '240*240*2/3600';

use Test::More;

{
    like ( $str, qr{^(\d+[*/])+(\d+)$}, 'Check regex' );
    done_testing;
}
tab@music4:~/Pianoforte/Development/Perlmonks 12:19:55 $ prove !$
prove 11154494.pl
11154494.pl .. ok   
All tests successful.
Files=1, Tests=1,  0 wallclock secs ( 0.02 usr  0.01 sys +  0.06 cusr  0.00 csys =  0.09 CPU)
Result: PASS
tab@music4:~/Pianoforte/Development/Perlmonks 12:19:58 $

##</code><code>##

tab@music4:~/Pianoforte/Development/Perlmonks 12:33:45 $ cat !$
cat 11154494-2.pl
#!/usr/bin/perl

use strict;
use warnings;

my $str = '240*240*2/3600';

use Test::More;

{
    like ( $str, qr{^(\d+\*){2}(\d+)/(\d+)$}, 'Check regex' );
    done_testing;
}
tab@music4:~/Pianoforte/Development/Perlmonks 12:33:50 $ prove !$
prove 11154494-2.pl
11154494-2.pl .. ok   
All tests successful.
Files=1, Tests=1,  0 wallclock secs ( 0.02 usr  0.01 sys +  0.05 cusr  0.00 csys =  0.08 CPU)
Result: PASS
tab@music4:~/Pianoforte/Development/Perlmonks 12:33:58 $