At 09 25, Shiyun left Town U and cycled towards Town V. Betty left Town U and cycled towards Town V at 09 55. Betty's cycling speed was 2 km/h faster than Shiyun. At 12 25, Betty caught up with Shiyun. Find the cycling speed of each cyclist.
- Shiyun
- Betty
(a)
Duration that Betty cycled from 09 55 to 12 25
= 2
3060 = 2
12 h
Distance that Betty cycled more than Shiyun
= 2
12 x 2
= 5 km
However, since Shiyun left 30 minutes earlier than Betty and Betty caught up with Shiyun, it means that Shiyun has cycled 5 km in 30 min.
1 h = 60 min
30 min = 30 ÷ 60 =
12 h
Shiyun's cycling speed
= 5 ÷
12 = 5 x
21 = 10 km/h
(b)
Betty's cycling speed
= 10 + 2
= 12 km/h
Answer(s): (a) 10 km/h ; (b) 12 km/h
