Dana left home at 11.10 a.m. and drove towards the suburb. 2 hours later, her grandfather left their home and drove towards the same suburb at 96 km/h. When the grandfather reached the suburb at 5.10 p.m., Dana had another 3 km to travel. What was Dana’s average speed? Express your answer in mixed number.
Time that the Dana's grandfather started driving = 1.10 p.m.
Duration that Dana's grandfather drove from 1.10 p.m. to 5.10 p.m. = 4 h

Distance that Dana's grandfather travelled
= 4 x 96
= 384 km

Distance that Dana travelled by the time her grandfather reached the city
= 384 - 3
= 381 km

Time that Dana took to travel 381 km = 6 h

Dana's average speed
= 381 ÷ 6
= 63¹₂ km/h

Answer(s): 63¹₂ km/h