At 8 a.m., Vaidev started from City B and travelled towards City C and his speed remained constant throughout. At 9 a.m., Eva started her journey from City B towards City C at an average speed of 90 km/h. Eva overtook Vaidev at 1 p.m. After overtaking, Eva carried on her journey at the same average speed and reached at City C at 2:40 p.m.
- Find Vaidev'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 Eva had travelled until Eva overtook Vaidev
= 4 x 90
= 360 km
From 8 a.m. to 1 p.m. = 5 h
Vaidev's average speed
= 360 ÷ 5
= 72 km/h
(b)
From 9 a.m. to 2:40 p.m. = 5 h 40 min
1 h = 60 min
5 h 40 min = 5
40 60
h = 5
23 h
Distance between the two cities
= 5
23 x 90
=
173 x 90
= 510 km
Answer(s): (a) 72 km/h; (b) 510 km