Answer:
[tex]P(A\cup B \cup C)=89[/tex]
Step-by-step explanation:
From the question we are told that:
Believed in UFO's [tex]A=42[/tex]
Believed in Ghosts [tex]B=45[/tex]
Believed in Bigfoot [tex]C=21[/tex]
Believed in UFO's & Ghosts [tex]A&B=11[/tex]
Believed in Ghosts & Bigfoot [tex]B&C=6[/tex]
Believed in UFO's & Bigfoot [tex]A&B=4[/tex]
Believed in ALL [tex]A&B&C=2[/tex]
Generally with a well detailed Set diagram of the Number of People that that believed in at least one of them is mathematically given by
[tex]P(A\cup B \cup C)=n(A\cap C)-n(B\cap C) +n(A\cap B \cap C)[/tex]
[tex]P(A\cup B \cup C)=42+45+21-11-6-4+2[/tex]
[tex]P(A\cup B \cup C)=89[/tex]
