In "The Grapes of Wrath," the estimate "fifty-sixty" is translated into Spanish (in "Las Uvas de la Ira") as "cincuenta y seis" (56).
Apparently the translator thought "fifty-sixty" was a typo (that what was meant was "fifty-six"). Is the rough estimate expressed thus in English unknown in Spanish? Is that why the translator made that assumption?
e.g., when English (American English?) speakers say something like this, it could be in the form: "I see fifty-sixty cars go by here every day." and what they mean by that is, "I see fifty to sixty cars go by here every day."