Jane left home at 11.55 a.m. and drove towards the suburb. 2 hours later, her older brother left their home and drove towards the same suburb at 96 km/h. When the older brother reached the suburb at 6.55 p.m., Jane had another 4 km to travel. What was Jane’s average speed? Express your answer in mixed number.
Time that the Jane's older brother started driving = 1.55 p.m.
Duration that Jane's older brother drove from 1.55 p.m. to 6.55 p.m. = 5 h

Distance that Jane's older brother travelled
= 5 x 96
= 480 km

Distance that Jane travelled by the time her older brother reached the city
= 480 - 4
= 476 km

Time that Jane took to travel 476 km = 7 h

Jane's average speed
= 476 ÷ 7
= 68 km/h

Answer(s): 68 km/h