Min left home at 11.30 a.m. and drove towards the seaside resort. 3 hours later, her older sister left their home and drove towards the same seaside resort at 94 km/h. When the older sister reached the seaside resort at 7.30 p.m., Min had another 4 km to travel. What was Min’s average speed? Express your answer in mixed number.
Time that the Min's older sister started driving = 2.30 p.m.
Duration that Min's older sister drove from 2.30 p.m. to 7.30 p.m. = 5 h

Distance that Min's older sister travelled
= 5 x 94
= 470 km

Distance that Min travelled by the time her older sister reached the city
= 470 - 4
= 466 km

Time that Min took to travel 466 km = 8 h

Min's average speed
= 466 ÷ 8
= 58¹₄ km/h

Answer(s): 58¹₄ km/h