Clue 3 

 1.  Gather 20 of the completed four-patch units and the twenty 6 1/2" x 6 1/2" feature squares.  2.  Sew these together as shown.  Pay close attention to this stop, making sure to position the small feature square in the Four-Patch unit against the upper-right corner of the large feature square.  Press the seam allowances toward the feature squares.  This is unit A.
Mystery Quilt

Clue 4

1.  Gather the remaining 20 Four-Patch units and the twenty 6 1/2" x 6 1/2" coordinate squares.  2.  Sew these together as shown.  Again, pay close attention, making sure to position the small coordinate square in the Four-Patch unit against the lower-left corner of the large coordinate square.  Press the seam allowances toward the feature square.  This is unit B.

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