At 7 a.m., Daniel started from City G and travelled towards City H and his speed remained constant throughout. At 9 a.m., Abi started her journey from City G towards City H at an average speed of 81 km/h. Abi overtook Daniel at 1 p.m. After overtaking, Abi carried on her journey at the same average speed and reached at City H at 1:20 p.m.
- Find Daniel'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 Abi had travelled until Abi overtook Daniel
= 4 x 81
= 324 km
From 7 a.m. to 1 p.m. = 6 h
Daniel's average speed
= 324 ÷ 6
= 54 km/h
(b)
From 9 a.m. to 1:20 p.m. = 4 h 20 min
1 h = 60 min
4 h 20 min = 4
20 60
h = 4
13 h
Distance between the two cities
= 4
13 x 81
=
133 x 81
= 351 km
Answer(s): (a) 54 km/h; (b) 351 km