I have learned about Venn diagrams … having a hard time remembering what to do.
Hi malainacain. Well, there's four different categories of people, in this exercise.
Those who donate
Those who help
Those who help and donate
Those who do not help and do not donate
Hints: Two partially-overlapping circles create four regions, one for each category of people. The four regions in the Venn diagram are:
The region outside both circles
The region inside the left circle that does not include the overlap
The region inside the right circle that does not include the overlap
The overlap
You decide which of the two, complete circles holds the people who donate. Then, label both circles.
Remember, each circle has two parts: the overlap and the remaining part.
How many people are in the overlap region? On the diagram, write that number inside the overlap.
Use that value to determine the number of people in the remaining part of each circle.
Let us know how far you get.
PS: Forget about what I'd said in my first reply about writing and solving a system of equations. That's unnecessary. (I'd been thinking of something else because I hadn't drawn the diagram.) Glad I caught that goof, before Jomo could.
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