Posted by Sue Jackson on .
A poll was taken of 100 students on how they got to campus. 33 drove alone, 35 rode in a carpool, 26 rode public transportation, 6 used both carpool and public transportation, 8 used both a carpool, 6 used buses as well as their own cars, 5 used all three methoda. How many are not using any of the treee?

Algebra 
Steve,
assuming all you need is confirmation of the answer you obtained through your hard work,
21