A poll was taken of 100 students at a commuter campus to find out how they got to campus. The results were as follows:
30 said they drove alone.
32 rode in a carpool.
34 rode public transportation.
8 used both carpools and public transportation.
4 used both a carpool and sometimes their own cars.
5 used buses as well as their own cars.
3 used all three methods.
How many used none of the above-mentioned means of transportation?
Review Venn diagrams, and you will see that the number of students who used any or all of the means is
(30+32+34)-(8+4+5)+3 = 82
So 18 used none