At 7 a.m., Zane started from City X and travelled towards City Y and his speed remained constant throughout. At 9 a.m., Gem started her journey from City X towards City Y at an average speed of 66 km/h. Gem overtook Zane at 1 p.m. After overtaking, Gem carried on her journey at the same average speed and reached at City Y at 2:30 p.m.
- Find Zane'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 Gem had travelled until Gem overtook Zane
= 4 x 66
= 264 km
From 7 a.m. to 1 p.m. = 6 h
Zane's average speed
= 264 ÷ 6
= 44 km/h
(b)
From 9 a.m. to 2:30 p.m. = 5 h 30 min
1 h = 60 min
5 h 30 min = 5
30 60
h = 5
12 h
Distance between the two cities
= 5
12 x 66
=
112 x 66
= 363 km
Answer(s): (a) 44 km/h; (b) 363 km