Nidhi Pandey, resident of Antop Hill area, was rushed to Sion hospital where she was declared dead on arrival.
Police said the incident happened at around 10 AM when she was returning from her fitness session at a gym. She was hit by a speeding bus while walking on the road listening to music, not paying attention to the oncoming traffic.
Even more tragically, while she was lying on the ground, two other buses ran over her, police said.
A passer-by alerted the police, but nobody volunteered to take her to the hospital until the police van arrived.
"The golden time was wasted," said a police official.
Police have arrested Harishchanra Argade, the driver of the first bus.
Pandey had recently cleared her HSC examination with 85 per cent marks.