Olivia left home at 10.55 a.m. and drove towards the province. 3 hours later, her uncle left their home and drove towards the same province at 89 km/h. When the uncle reached the province at 5.55 p.m., Olivia had another 6 km to travel. What was Olivia’s average speed? Express your answer in mixed number.
Time that the Olivia's uncle started driving = 1.55 p.m.
Duration that Olivia's uncle drove from 1.55 p.m. to 5.55 p.m. = 4 h

Distance that Olivia's uncle travelled
= 4 x 89
= 356 km

Distance that Olivia travelled by the time her uncle reached the city
= 356 - 6
= 350 km

Time that Olivia took to travel 350 km = 7 h

Olivia's average speed
= 350 ÷ 7
= 50 km/h

Answer(s): 50 km/h