The eight months he has already spent in a home since his arrest will be knocked off his sentence.
He was a few months short of 18 at the time of the crime which incensed India and forced the introduction of tougher laws for sexual crimes.
The student's parents broke down after the verdict. "We feel cheated. It's a crime to be born a girl in this country," said the girl's father. (Read) The parents said they will appeal against the verdict in a higher court.
The convict, who is now 18, has been acquitted of charges of attempted murder of the student's male friend, who was with her on the bus and was assaulted with an iron rod to prevent him from helping her.
He belongs to a village in Uttar Pradesh and had moved to Delhi when he was 11 to start working. (Read: In a village, a mother hopes someday her son will return)
Of the five adults who were arrested, one committed suicide in jail in March. The others are being tried by a special fast-track court and could face the death sentence if convicted.
The verdict on them is expected in mid-September.
On December 16, the young woman and her male friend were allegedly tricked into boarding an off-duty bus. The police say the men on board raped and brutalised the woman and savagely beat the man before dumping them naked on the roadside. The woman died from her injuries two weeks later in a Singapore hospital.
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