A person left a city P to city Q in car at 8.00 a.m. He travelled at a speed of 90 km/hr for 3 hours. After that the speed was reduced to 80 km/hr. If the distance between the cities is 510 kms., at what time did he reach city Q ?
1
1.00 p.m.
2
1.30 p.m.
3
2.00 p.m.
4
12.30 p.m.