Manny will eat 1 piece.
Aaron will eat 0 pieces.
Kai will eat twice as much as Manny, so he will eat 2 * 1 = <<2*1=2>>2 pieces.
Raphael will eat half as much as Manny, so he will eat 1 * 1/2 = 1/2 piece.
Lisa will eat 2 pieces plus the remainder of Raphael’s piece, so she will eat 2 + 1/2 = 2 1/2 pieces.
Together, they will eat 1 + 0 + 2 + 1/2 + 2 1/2 = 1 + 2 + 3 = 6 pieces.
Thus, Manny should cut his lasagna into 6 pieces.
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