Error of Use of undefined constant to_f – assumed 'to_f'

I turned on the Debug mode on my site since it was completely blanked out white.
These are the errors I’m getting right now and I’ve tried so many things to fix it but can’t seem to do so.

[22-Jul-2015 13:30:19 UTC] PHP Notice: Use of undefined constant to_f – assumed ‘to_f’ in /home/korzcons/public_html/wp-includes/default-filters.php on line 14
[22-Jul-2015 13:30:22 UTC] PHP Notice: Use of undefined constant to_f – assumed ‘to_f’ in /home/korzcons/public_html/wp-includes/default-filters.php on line 14

If anyone could help, that’d be great