Jade left home at 10.50 a.m. and drove towards the province. 3 hours later, her cousin left their home and drove towards the same province at 84 km/h. When the cousin reached the province at 6.50 p.m., Jade had another 4 km to travel. What was Jade’s average speed? Express your answer in mixed number.
Time that the Jade's cousin started driving = 1.50 p.m.
Duration that Jade's cousin drove from 1.50 p.m. to 6.50 p.m. = 5 h

Distance that Jade's cousin travelled
= 5 x 84
= 420 km

Distance that Jade travelled by the time her cousin reached the city
= 420 - 4
= 416 km

Time that Jade took to travel 416 km = 8 h

Jade's average speed
= 416 ÷ 8
= 52 km/h

Answer(s): 52 km/h