Additional district judge (I), Neeraj Kumar Srivastav, has found Vijay Kumar and Ajay Mishra guilty of the crime under sections of the Indian Penal Code and pronounced the quantum of the sentence against them on Saturday.
The judge also slapped a fine of Rs 10,000 on them, additional public prosecutor Subhas Prasad said.
On defaulting in payment of the penalty amount, the convicts will have to serve an additional jail term of six months, he said.
The incident had taken place on October 30, 2017 when the victim had gone to Simdega town to purchase medicines.
The duo had kidnapped the victim and raped her at Ranikudar Jhumki hills near the town, before dumping her near Kherantoli village in the district.
The woman had lodged an FIR with the Simdega police station, following which the two men were arrested.
The same court had on Friday sentenced 20 year-old Sonu Lohara to 20 years rigorous imprisonment, besides slapping a fine of Rs 10,000 on him for raping a teenage girl in Simdega last year, Prasad said.
Lohara was convicted under the Protection of Children from Sexual Offences Act and other sections of the Indian Penal Code.