At 8 a.m., Tommy started from City X and travelled towards City Y and his speed remained constant throughout. At 9 a.m., Nicole started her journey from City X towards City Y at an average speed of 80 km/h. Nicole overtook Tommy at 1 p.m. After overtaking, Nicole carried on her journey at the same average speed and reached at City Y at 2:15 p.m.
- Find Tommy's average speed in km/h.
- What is the distance between the two cities?
(a)
From 9 a.m. to 1 p.m. = 4 h
Distance that Nicole had travelled until Nicole overtook Tommy
= 4 x 80
= 320 km
From 8 a.m. to 1 p.m. = 5 h
Tommy's average speed
= 320 ÷ 5
= 64 km/h
(b)
From 9 a.m. to 2:15 p.m. = 5 h 15 min
1 h = 60 min
5 h 15 min = 5
15 60
h = 5
14 h
Distance between the two cities
= 5
14 x 80
=
214 x 80
= 420 km
Answer(s): (a) 64 km/h; (b) 420 km