Given that the area of parallelogram ABCD is 4 and O is the intersection of two diagonals, then the area of △ AOB is______ ．

According to the diagonal property of parallelogram, Ao is the middle line of △ abd, so s △ AOD = s △ AOB. Similarly, s △ AOB = s △ BOC = s △ cod, so s △ AOB = 14s parallelogram ABCD = 1

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