Question

We have 50 video gamers who share information about their favorite games. 20 people say that Borderlands II is their favorite game. 33 say their favorite game is Fortnite, while 19 declare Minecraft as their favorite game (note that a single person can have several favorite games). 15 people say that Borderlands and Fortnite are both favorites, while 10 say that both Borderlands and Minecraft are their favorites. Finally, 5 people declare all 3 of the games as their favorites. How many people declared Minecraft and Fortnite (exclusively) as their favorites?

Answer 1

2

Explanation:

Answer 2

2 people

Explanation:

Total number of people (n) = 50

Borderlands II (B) = 20

Fortnite (F) = 33

Minecraft (M) = 19

Borderlands and Fortnite (B&F) = 15

Borderlands and Minecraft (B&M)= 10

All games (B&M&F) = 5

The number of people that claimed more than one game as their favorite (X) is given by:

`X=M+B+F-n\\X=19+20+33-50\\X=22\ people`

Those people can be divided in B&F only, B&M only, M&F only and B&M&F:

`X=(B\&M-B\&M\&F)+(B\&F-B\&M\&F)+(M\&F-B\&M\&F)+B\&M\&F\\X=B\&M+B\&F+M\&F-2*B\&M\&F\\22=10+15+M\&F-2*5\\M\&F=7\ people`

7 people claimed that Minecraft and Fortnite were their favorites however, 5 of those people claimed all of the games as their favorite. Therefore, only 2 people declared Minecraft and Fortnite (exclusively) as their favorites.