At 09 20, Sarah left Town W and cycled towards Town X. Pamela left Town W and cycled towards Town X at 09 35. Pamela's cycling speed was 4 km/h faster than Sarah. At 11 20, Pamela caught up with Sarah. Find the cycling speed of each cyclist.
- Sarah
- Pamela
(a)
Duration that Pamela cycled from 09 35 to 11 20
= 1
4560 = 1
34 h
Distance that Pamela cycled more than Sarah
= 1
34 x 4
= 7 km
However, since Sarah left 15 minutes earlier than Pamela and Pamela caught up with Sarah, it means that Sarah has cycled 7 km in 15 min.
1 h = 60 min
15 min = 15 ÷ 60 =
14 h
Sarah's cycling speed
= 7 ÷
14 = 7 x
41 = 28 km/h
(b)
Pamela's cycling speed
= 28 + 4
= 32 km/h
Answer(s): (a) 28 km/h ; (b) 32 km/h