Contracts II
Restatement Second of Contracts § 240
Part Performances as Agreed Equivalents
If the performances to be exchanged under an exchange of promises can be apportioned into corresponding pairs of part performances so that the parts of each pair are properly regarded as agreed equivalents, a party's performance of his part of such a pair has the same effect on the other's duties to render performance of the agreed equivalent as it would have if only that pair of performances had been promised.
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