From The Primary Souces for the Life and Work of Hypatia of Alexandria, by Michael A.B. Deakin
It was once thought that the surviving Greek text of Diophantus' Arithmetic held portions due to Hypatia, but this hypothesis is no longer tenable. Further portions of this work have recently been unearthed, in Arabic translation. Comparison of the Greek and the Arabic versions make it clear that if any of Hypatia's work survives it is in the Arabic rather than the Greek. The most likely Hypatian material is the detailed checking that the solutions are valid.
For more discussion with translation of the original text, see J. Sesiano's Books IV to VII of Diophantus' Arithmetica (New York: Springer, 1982) and R. Rashed's Diophante: Les Arithmé tiques, Tome III, Livre IV; Tome IV, Livres V, VI, VII (Paris: Socié té d'é dition "Les belles lettres", 1984). Sesiano and Rashed are the two foremost authorities on this material, but they differ deeply and acrimoniously over many points. The question of Hypatia's involvement in this material is still very much under discussion.
From Hypatia's Mathematics: A Review of Recent Studies, by Edith Prentice Mendez