Hazel left home at 11.45 a.m. and drove towards the campsite. 2 hours later, her older brother left their home and drove towards the same campsite at 97 km/h. When the older brother reached the campsite at 6.45 p.m., Hazel had another 2 km to travel. What was Hazel’s average speed? Express your answer in mixed number.
Time that the Hazel's older brother started driving = 1.45 p.m.
Duration that Hazel's older brother drove from 1.45 p.m. to 6.45 p.m. = 5 h

Distance that Hazel's older brother travelled
= 5 x 97
= 485 km

Distance that Hazel travelled by the time her older brother reached the city
= 485 - 2
= 483 km

Time that Hazel took to travel 483 km = 7 h

Hazel's average speed
= 483 ÷ 7
= 69 km/h

Answer(s): 69 km/h