At 8 a.m., Sean started from City R and travelled towards City S and his speed remained constant throughout. At 10 a.m., Cindy started her journey from City R towards City S at an average speed of 66 km/h. Cindy overtook Sean at 2 p.m. After overtaking, Cindy carried on her journey at the same average speed and reached at City S at 4:40 p.m.
- Find Sean'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 Cindy had travelled until Cindy overtook Sean
= 4 x 66
= 264 km
From 8 a.m. to 2 p.m. = 6 h
Sean's average speed
= 264 ÷ 6
= 44 km/h
(b)
From 10 a.m. to 4:40 p.m. = 6 h 40 min
1 h = 60 min
6 h 40 min = 6
40 60
h = 6
23 h
Distance between the two cities
= 6
23 x 66
=
203 x 66
= 440 km
Answer(s): (a) 44 km/h; (b) 440 km