Shannon left home at 11.35 a.m. and drove towards the suburb. 2 hours later, her older sister left their home and drove towards the same suburb at 96 km/h. When the older sister reached the suburb at 4.35 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 older sister started driving = 1.35 p.m.
Duration that Shannon's older sister drove from 1.35 p.m. to 4.35 p.m. = 3 h

Distance that Shannon's older sister travelled
= 3 x 96
= 288 km

Distance that Shannon travelled by the time her older sister reached the city
= 288 - 5
= 283 km

Time that Shannon took to travel 283 km = 5 h

Shannon's average speed
= 283 ÷ 5
= 56³₅ km/h

Answer(s): 56³₅ km/h