use strict;
use warnings;

my @multi_array = map [split], <DATA>;
my @by_second = map {$_->[1] *= 1.1E3; $_;} @multi_array;
printf "%E %E %E\n", @{$_}[0..2] for @by_second;

__DATA__
1.10000E0 1.00000E0 1.00000E0
2.20000E0 2.00000E0 2.00000E0
3.30000E0 3.00000E0 3.00000E0