How to hide date and time in pages of TwentyTwelve theme?

Open and edit content-page.php.  Remove the following code in it.

<footer class="entry-meta">
<?php edit_post_link( __( 'Edit', 'twentytwelve' ), '<span class="edit-link">', '</span>' ); ?>
</footer><!-- .entry-meta -->

Upload/save the file file.  From now, you won’t see the date and time display in pages.