Solving Union/Intersection Problem: 554 is Absurd!

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If I know:

[itex]|A \cup B \cup C|[/itex] = 1000
[itex]|A|[/itex] = 344
[itex]|B|[/itex] = 572
[itex]|C|[/itex] = 296
[itex]|A \cap B|[/itex] = 301
[itex]|B \cap C|[/itex] = 252
[itex]|A \cap C|[/itex] = 213

and I use the standard formula to compute [itex]|A \cap B \cap C|[/itex], I get 554, which is absurd. Can someone tell me what's wrong here? Is there something inconsistent in the initial data we're given? If so, I can't find it...
 
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How did you get 554?
 
mathman said:
How did you get 554?

Using the following formula:

[tex]|A \cup B \cup C| = |A| + |B| + |C| - |A \cap B| - |B \cap C| - |A \cap C| + |A \cap B \cap C|[/tex]
 
AxiomOfChoice said:
Using the following formula:

[tex]|A \cup B \cup C| = |A| + |B| + |C| - |A \cap B| - |B \cap C| - |A \cap C| + |A \cap B \cap C|[/tex]

So 1000= 344+ 572+ 296- 301- 572- 296+ x.

Then you appear to have just done the arithmetic wrong. Solving this equation for x does not give anything like 554!
 
HallsofIvy said:
So 1000= 344+ 572+ 296- 301- 572- 296+ x.

Then you appear to have just done the arithmetic wrong. Solving this equation for x does not give anything like 554!

...are you quite sure what you wrote is correct?
 
Final analysis: The data is wrong. |A|+|B|+|C|=1212. This allows only 212 for any overlap. Since each of the pairwise intersections is more, this is impossible.

Note: minor error in the 1000= statement, the -296 should be -213, but it doesn't change the analysis.
 

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