Shannon left home at 11.20 a.m. and drove towards the countryside. 2 hours later, her father left their home and drove towards the same countryside at 92 km/h. When the father reached the countryside at 5.20 p.m., Shannon had another 5 km to travel. What was Shannon’s average speed? Express your answer in mixed number.
Time that the Shannon's father started driving = 1.20 p.m.
Duration that Shannon's father drove from 1.20 p.m. to 5.20 p.m. = 4 h

Distance that Shannon's father travelled
= 4 x 92
= 368 km

Distance that Shannon travelled by the time her father reached the city
= 368 - 5
= 363 km

Time that Shannon took to travel 363 km = 6 h

Shannon's average speed
= 363 ÷ 6
= 60¹₂ km/h

Answer(s): 60¹₂ km/h