At 9 a.m., Jenson started from City J and travelled towards City K and his speed remained constant throughout. At 10 a.m., Ivory started her journey from City J towards City K at an average speed of 84 km/h. Ivory overtook Jenson at 1 p.m. After overtaking, Ivory carried on her journey at the same average speed and reached at City K at 3:25 p.m.
- Find Jenson's average speed in km/h.
- What is the distance between the two cities?
(a)
From 10 a.m. to 1 p.m. = 3 h
Distance that Ivory had travelled until Ivory overtook Jenson
= 3 x 84
= 252 km
From 9 a.m. to 1 p.m. = 4 h
Jenson's average speed
= 252 ÷ 4
= 63 km/h
(b)
From 10 a.m. to 3:25 p.m. = 5 h 25 min
1 h = 60 min
5 h 25 min = 5
25 60
h = 5
512 h
Distance between the two cities
= 5
512 x 84
=
6512 x 84
= 455 km
Answer(s): (a) 63 km/h; (b) 455 km