After graduation (Abitur) in March 1931 she studied mathematics and physics at the University of Berlin and got her Doctor of Philosophy in Mathematics at 1936 with Issai Schur as supervisor (Das Turnierproblem für Spiele zu je dreien, The tournament problem for three person games).
Her dissertation was valued opus valde laudabile(de). Being Jewish she emigrated through Italy to Palestine, arriving 1938. Between the years 1939–1942 she worked in a bank and later as a lawyer"s secretary and translator in Tel Aviv.
Peltesohn solved the Difference Problems of Lothar Heffter (1896) in combinatorics in 1939.
A Difference Triple (a, b, c) is defined as three different elements from the set, whose sum equals zero () or for which one element equals the sum of the other two (). First Difference Problem of Heffter: Let.
Is there a partition of the set in difference triples? Second Difference Problem of Heffter: Let. Is there a partition of the set in difference triples ? Following Peltesohn, such a partition exists with the exception of the case v = 9.
An example of the partition for is: (with ) and (with ).
The solution of the Difference Problem of Heffter also gives a construction of cyclic Steiner triple systems Jahresbericht Deutsche Mathematikervereinigung (Department of Motor Vehicles) 71: 171–228. in particular pages 188–189.