At 9 a.m., Brandon started from City L and travelled towards City M and his speed remained constant throughout. At 10 a.m., Jade started her journey from City L towards City M at an average speed of 70 km/h. Jade overtook Brandon at 2 p.m. After overtaking, Jade carried on her journey at the same average speed and reached at City M at 5:30 p.m.
- Find Brandon's average speed in km/h.
- What is the distance between the two cities?
(a)
From 10 a.m. to 2 p.m. = 4 h
Distance that Jade had travelled until Jade overtook Brandon
= 4 x 70
= 280 km
From 9 a.m. to 2 p.m. = 5 h
Brandon's average speed
= 280 ÷ 5
= 56 km/h
(b)
From 10 a.m. to 5:30 p.m. = 7 h 30 min
1 h = 60 min
7 h 30 min = 7
30 60
h = 7
12 h
Distance between the two cities
= 7
12 x 70
=
152 x 70
= 525 km
Answer(s): (a) 56 km/h; (b) 525 km