Dana left home at 11.45 a.m. and drove towards the suburb. 2 hours later, her mother left their home and drove towards the same suburb at 89 km/h. When the mother reached the suburb at 4.45 p.m., Dana had another 6 km to travel. What was Dana’s average speed? Express your answer in mixed number.
Time that the Dana's mother started driving = 1.45 p.m.
Duration that Dana's mother drove from 1.45 p.m. to 4.45 p.m. = 3 h

Distance that Dana's mother travelled
= 3 x 89
= 267 km

Distance that Dana travelled by the time her mother reached the city
= 267 - 6
= 261 km

Time that Dana took to travel 261 km = 5 h

Dana's average speed
= 261 ÷ 5
= 52¹₅ km/h

Answer(s): 52¹₅ km/h