"These are the last two oranges."
Translation:Das sind die letzten zwei Orangen.
frauen is never correct.
starke Frauen (with the noun capitalised) is correct if there is no article before the adjective -- then it takes strong inflection, which is -e in the plural.
If you wanted to say not "strong women" (in general) but instead "the strong women" (a particular group), then it would be die starken Frauen with weak inflection -en after the definite article.
Whether to use strong, weak, or mixed inflection for an adjective depends on whether there is a determiner (e.g. definite article, possessive, ...) in front of the adjective or not, and if so, what kind of determiner.