Bigfoot
13
UFO
29
Ghosts
30
2
4
9
2
Discussion 1 Sets
2 - Believed in all of them
11 - Believed in UFOs and Ghosts = 11-2= 9
4- Belived in UFOs and Bigfoot = 4-2= 2
6 - Believed in Ghosts and Bigfoot = 6-2 = 4
which means, Ghosts = 15-45=30
Bigfoot = 21-8=13 and
UFOs 42-13=29
The people that believe in at least one of these things = 29+9+2+2+9+30+13=89
Therefore, at least 89 people believed in at least one of these things.
