use Modern::Perl;

my @test = (
    "text text text 1 text",
    "1 text text text 2 text 3",
    "text 1 text text 2 text",
    "text text text 1 text 2 3.0",
    "1 2 3 4 5 6 7 8 9 10 11",
    "text text 4.5 text text"
);

for (@test) {
    say "$_: $1" if /(\d+)\.?\d*?\D*?$/;
}

##</code><code>##

text text text 1 text: 1
1 text text text 2 text 3: 3
text 1 text text 2 text: 2
text text text 1 text 2 3.0: 3
1 2 3 4 5 6 7 8 9 10 11: 11
text text 4.5 text text: 4