At 09 15, Sarah left Town Q and cycled towards Town R. Yoko left Town Q and cycled towards Town R at 09 55. Yoko's cycling speed was 9 km/h faster than Sarah. At 11 15, Yoko caught up with Sarah. Find the cycling speed of each cyclist.
- Sarah
- Yoko
(a)
Duration that Yoko cycled from 09 55 to 11 15
= 1
2060 = 1
13 h
Distance that Yoko cycled more than Sarah
= 1
13 x 9
= 12 km
However, since Sarah left 40 minutes earlier than Yoko and Yoko caught up with Sarah, it means that Sarah has cycled 12 km in 40 min.
1 h = 60 min
40 min = 40 ÷ 60 =
23 h
Sarah's cycling speed
= 12 ÷
23 = 12 x
32 = 18 km/h
(b)
Yoko's cycling speed
= 18 + 9
= 27 km/h
Answer(s): (a) 18 km/h ; (b) 27 km/h
