At 8 a.m., Rael started from City E and travelled towards City F and his speed remained constant throughout. At 10 a.m., Tammy started her journey from City E towards City F at an average speed of 90 km/h. Tammy overtook Rael at 2 p.m. After overtaking, Tammy carried on her journey at the same average speed and reached at City F at 2:20 p.m.
- Find Rael'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 Tammy had travelled until Tammy overtook Rael
= 4 x 90
= 360 km
From 8 a.m. to 2 p.m. = 6 h
Rael's average speed
= 360 ÷ 6
= 60 km/h
(b)
From 10 a.m. to 2:20 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 90
=
133 x 90
= 390 km
Answer(s): (a) 60 km/h; (b) 390 km