Solving Union/Intersection Problem: 554 is Absurd!

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If I know:

|A \cup B \cup C| = 1000
|A| = 344
|B| = 572
|C| = 296
|A \cap B| = 301
|B \cap C| = 252
|A \cap C| = 213

and I use the standard formula to compute |A \cap B \cap C|, 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:

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

|A \cup B \cup C| = |A| + |B| + |C| - |A \cap B| - |B \cap C| - |A \cap C| + |A \cap B \cap C|

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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