At 7 a.m., Ahmad started from City H and travelled towards City J and his speed remained constant throughout. At 9 a.m., Winnie started her journey from City H towards City J at an average speed of 87 km/h. Winnie overtook Ahmad at 1 p.m. After overtaking, Winnie carried on her journey at the same average speed and reached at City J at 6:20 p.m.
- Find Ahmad'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 Winnie had travelled until Winnie overtook Ahmad
= 4 x 87
= 348 km
From 7 a.m. to 1 p.m. = 6 h
Ahmad's average speed
= 348 ÷ 6
= 58 km/h
(b)
From 9 a.m. to 6:20 p.m. = 9 h 20 min
1 h = 60 min
9 h 20 min = 9
20 60
h = 9
13 h
Distance between the two cities
= 9
13 x 87
=
283 x 87
= 812 km
Answer(s): (a) 58 km/h; (b) 812 km