Three Yorkshire neighbouring estates were to be offered for sale. 
Each estate was square in shape, and they joined one another at their corners, just as shown in the diagram. 
Estate A contains exactly 370 acres, B contains 116 acres, and C 74 acres.

Now, the little triangular bit of land enclosed by the three square estates was not offered for sale, and, for no reason in particular, I became curious as to the area of that piece. 

How many acres did it contain?

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