Question: How old was Rachel when Jacob first met her? When they were married? When she died?
Answer: Seder Olam Rabbah 74:4 says that Rachel was 22 when she married Yaakov (Jacob), and this seems to be the primary opinion, although I have seen one source suggest that Rachel was 5 when they met making her 12 at the time of marriage. Rachel and Leah were twin sisters. Jacob married Leah and Rachel a week apart although he worked 7 years for each of them.
Rachel died at age 36. Remember that the marriages of all the Jewish Patriarchs and Matriarchs were arranged and designed by G-d in order to create the Jewish Nation that would be coming. The Patriarchs were also prophets and had great insight into their mission in this world and what G-d was expecting from them.
Regards, Eliahu Levenson