Elyse left home at 10.35 a.m. and drove towards the suburb. 3 hours later, her younger brother left their home and drove towards the same suburb at 88 km/h. When the younger brother reached the suburb at 5.35 p.m., Elyse had another 2 km to travel. What was Elyse’s average speed? Express your answer in mixed number.
Time that the Elyse's younger brother started driving = 1.35 p.m.
Duration that Elyse's younger brother drove from 1.35 p.m. to 5.35 p.m. = 4 h

Distance that Elyse's younger brother travelled
= 4 x 88
= 352 km

Distance that Elyse travelled by the time her younger brother reached the city
= 352 - 2
= 350 km

Time that Elyse took to travel 350 km = 7 h

Elyse's average speed
= 350 ÷ 7
= 50 km/h

Answer(s): 50 km/h