Pamela left home at 11.20 a.m. and drove towards the city. 2 hours later, her older brother left their home and drove towards the same city at 98 km/h. When the older brother reached the city at 5.20 p.m., Pamela had another 5 km to travel. What was Pamela’s average speed? Express your answer in mixed number.
Time that the Pamela's older brother started driving = 1.20 p.m.
Duration that Pamela's older brother drove from 1.20 p.m. to 5.20 p.m. = 4 h

Distance that Pamela's older brother travelled
= 4 x 98
= 392 km

Distance that Pamela travelled by the time her older brother reached the city
= 392 - 5
= 387 km

Time that Pamela took to travel 387 km = 6 h

Pamela's average speed
= 387 ÷ 6
= 64¹₂ km/h

Answer(s): 64¹₂ km/h