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**austin81****Member**- Registered: 2005-03-21
- Posts: 39

A venn diagram with 1 set has 2 regions

A venn diagram with 2 sets has 4 regions

A venn diagram with 3 sets has 8 regions

How many regions would a venn diagram with 4 sets have? Can such a diagram be drawn?If yes,then draw it

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,684

Draw it here? With my keyboard?

YES it can be done. Venn himself managed it using ellipses. I have re-created it here:

I count 16 regions including the "outside" region.

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**Roraborealis****Member**- Registered: 2005-03-17
- Posts: 1,594

What would you use that for?

School is practice for the future. Practice makes perfect. But - nobody's perfect, so why practice?

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,684

Looks nice on the wall.

Or, you could use it organize people or things based on four qualities. For example, your friends could be tall, or blond, or smart, or fat. Some could be tall AND blond, or tall AND smart, or all four, etc ...

As you can see, there are 4 ellipses that overlap each other. Each ellipse is a quality, for example "tall". The lower left ellipse could mean "tall", and the one above it could be "blond", and the two on the right could be "smart" and "fat".

Where the ellipses overlap is where you would place your friends with more than one quality, and in the middle (where they all overlap) is where you would put your friend(s) who have ALL those qualities.

Have a go, and see what all the possible combinations would be, and make sure that there is a place on the diagram for each of them.

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**austin81****Member**- Registered: 2005-03-21
- Posts: 39

How can I thank u!!

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**austin81****Member**- Registered: 2005-03-21
- Posts: 39

Oh! before I forget, there are supposed to be 16 regions if one were to follow the logic in it

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