what's the frequency of the letter "a" in:
q: how do i hide some of the questions in the graphical summary of sharepoint 2013 survey? seems like this should be do-able using .css in a cewp, with something like:
div [#h3.ms-standardheader, .ms-vb$="the next question"] {display: none;}

##h3.ms-standardheader, .ms-vb {display: none;}

will hide the text for all questions.  i just want to hide questions that end with "the next question" string.

a: according to the specification you cant match content within an element.
jquery solution
you could use the :contains selector to get elements based on their content, the following example demonstrates how to hide question:
var q = $('h3.ms-standardheader,.ms-vb:contains("the next question")');
q.hide();  //hide question caption
q.next().hide(); //hide question results

update
use .ready() to execute the code when a page is rendered:
$(function() {
   var q = $('#h3.ms-standardheader, .ms-vb:contains("the next question")'); 
   q.hide(); //hide question caption 
   q.next().hide(); //hide question results
});


user
The given text has 43 "a"s.
assistant