Jordan picked 54/3 = <<54/3=18>>18 ripe mangoes.
He picked 54 - 18 = <<54-18=36>>36 unripe mangoes.
Jordan gave 36 - 16 = <<36-16=20>>20 unripe mangoes to his sister.
Jordan's sister can make 20/4 = <<20/4=5>>5 jars of pickled mangoes.
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