200 people were asked which of these grand slam tournaments that they have attended. The tournaments inquired about were: US Open, Wimbledon, or Australian Open.
- 30 people have not attended any of these tournaments.
- 10 people have been to all thee tournaments.
- 25 people have been to Wimbledon and the Australian Open.
- 20 people have been to the US Open and the Australian Open but not to Wimbledon.
- 65 people have been to exactly two of the tournaments.
- 165 people have been to the US Open or to Wimbledon.
- 120 people have been to Wimbledon or to the Australian Open.
I do not understand how 50 is in the US open only, 40 Wimbledon only, and 5 Australian open only. Please explain. Thank you.
I know that:
W+U=90 and W+A=45. How can they say these numbers. To have a system I would need to have the same the same letters.