A non-numeric value encountered in..

I’m getting the following error about the theme..

A non-numeric value encountered in /home/progtur/public_html/blog/wp-content/themes/engine/functions/loop.php on line 75

`69 #defaults
70 $cats = ”;
71 $updatepagination=1;
72 $perpage = $args[‘posts_per_page’];
73 $posts_shown = $itposts->found_posts;
74 if($posts_shown > $perpage) $posts_shown = $perpage;
75 $percol = ceil($posts_shown / 4);
76 #articles per column for new articles panel
77 $first = true;
78 if ($itposts->have_posts()) : while ($itposts->have_posts()) :
$itposts->the_post(); $p++; `

code block above with the error.

I will be glad if you help me.

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