I'm stumped at this question. I'm not sure what forum I should post this in
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Do you know how to use Venn diagram?
Please share your work/thoughts about this assignment.
HallsofIvy
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You are told that "No one who plays on the hockey team plays on the other two teams" so you can immediately discount the 45 members of the hockey team. That leaves 87- 45= 42 people who were on the soccer or track teams or both. If the two teams had completely different players, there would be a total of 27+ 24= 51. But there are only 42 present! What does that tell you about the "missing" 51- 42= 9 people?
pka
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Here is a non-Venn approach.
Notation: \(\displaystyle \#(X)\) stands for the number of players on the \(\displaystyle X\) team.
A basic counting rule is the inclusion/exclusion principle.
Thus \(\displaystyle \#(H\cup S\cup T)=\#(H)+\#(S)+\#(T)-\#(H\cap S)-\#(H\cap T)-\#(S\cap T)+\#(H \cap S\cap T )\)
Do we know the total (the LHS)?
Do we know that some of the RHS are zeros? WHY?
Notation: \(\displaystyle \#(X)\) stands for the number of players on the \(\displaystyle X\) team.
A basic counting rule is the inclusion/exclusion principle.
Thus \(\displaystyle \#(H\cup S\cup T)=\#(H)+\#(S)+\#(T)-\#(H\cap S)-\#(H\cap T)-\#(S\cap T)+\#(H \cap S\cap T )\)
Do we know the total (the LHS)?
Do we know that some of the RHS are zeros? WHY?