Your output doesn't seem to match your description, but I think you want something like this: 
use strict;
use warnings;

while (<DATA>) {
    next unless /\S/;
    my @c = split;
    my $p = 0.7 * $c[2];
    print if ($c[4] - $c[3] > $p)
}

__DATA__
aa 22 310 1 300

ab 40 200 2 228

ac 51 230 10 241

df 23 240 22 242

ef 34 370 24 282

gh 24 125 22 210

df 76 290 11 232

wq 13 170 20 180

ss 89 288 12 270

[download]

prints out: 

aa 22 310 1 300
ab 40 200 2 228
ac 51 230 10 241
df 23 240 22 242
gh 24 125 22 210
df 76 290 11 232
wq 13 170 20 180
ss 89 288 12 270

[download]

In reply to Re: to print l columnwise and subtraction by toolic
in thread to print l columnwise and subtraction by vis1982

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