Raeann left home at 11.20 a.m. and drove towards the countryside. 2 hours later, her uncle left their home and drove towards the same countryside at 90 km/h. When the uncle reached the countryside at 4.20 p.m., Raeann had another 3 km to travel. What was Raeann’s average speed? Express your answer in mixed number.
Time that the Raeann's uncle started driving = 1.20 p.m.
Duration that Raeann's uncle drove from 1.20 p.m. to 4.20 p.m. = 3 h

Distance that Raeann's uncle travelled
= 3 x 90
= 270 km

Distance that Raeann travelled by the time her uncle reached the city
= 270 - 3
= 267 km

Time that Raeann took to travel 267 km = 5 h

Raeann's average speed
= 267 ÷ 5
= 53²₅ km/h

Answer(s): 53²₅ km/h