Here is the code;

To use this code open your functions.php and paste this code into end of file.

function is_old_post($post_id=null){
   $days = 15;
   global $wp_query;
   if(is_single() || is_page()) {
      if(!$post_id) {
         $post_id = $wp_query->post->ID;
      }
      $current_date = time();
      $offset = $days *60*60*24;
      $post_id = get_post($post_id);
      $post_date = mysql2date('U',$post_id->post_date);
      $cunning_math = $post_date + $offset;
      $test = $current_date - $cunning_math;
      if($test > 0){
         $return = true;
      }else{
         $return = false;
      }
   }else{
      $return = false;
   }
   return $return;
}

After that use this code for show your ads…

<?php if(is_old_post()){ ?>
INSERT AD CODE HERE
<?php } ?>

This function show ads on your 15 days old posts. To change this simply change $days value

Related posts:

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2. Disable Comments on 30-day older posts
3. Related Posts, Without any Plugin!

We make changes on your themes functions.php. If your theme have no functions.php simply create one and paste this code in your file ;

Here is the Code;

<?php
 function insertAds($content) {
 $content = $content.'<hr /><a href="http://www.wpfunc.com">Hola, Awesome, Quick, Simple WordPress Functions</a><hr />';
 return $content;
 }
 add_filter('the_excerpt_rss', 'insertAds');
 add_filter('the_content_rss', 'insertAds');
?>

If you change $content area (between <hr/> and <hr/>) you can change it with your google adsense code.

That’s All! Have a nice day!

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