Julie left home at 11.50 a.m. and drove towards the province. 2 hours later, her father left their home and drove towards the same province at 83 km/h. When the father reached the province at 5.50 p.m., Julie had another 5 km to travel. What was Julie’s average speed? Express your answer in mixed number.
Time that the Julie's father started driving = 1.50 p.m.
Duration that Julie's father drove from 1.50 p.m. to 5.50 p.m. = 4 h

Distance that Julie's father travelled
= 4 x 83
= 332 km

Distance that Julie travelled by the time her father reached the city
= 332 - 5
= 327 km

Time that Julie took to travel 327 km = 6 h

Julie's average speed
= 327 ÷ 6
= 54¹₂ km/h

Answer(s): 54¹₂ km/h