easy answer is yes… the not so easy answer is yes, but you have to modify the page template for it, which you would want to duplicate the template but in a child theme (if you are using one). Otherwise in the template file page-left-right.php located in the page-templates folder of the theme, there is a left column container with a span3 class and a right column span4 class. Then in between is the main content with a span5 class. You have to change these spans to what you want, as long as all three add up to 12 (because this theme is based on a 12 column grid). So if you want a left and right with a span 4, then your content will have to be span4. I recommend going left = span3, right=span3, then your main content is span6.
Make sure if you are using a child theme for theme modifications like this, that you duplicate not just the page template itself, but also the folder it’s in to maintain the same file structure of the parent theme.