At 06 20, Irene left Town E and cycled towards Town F. Zoe left Town E and cycled towards Town F at 06 50. Zoe's cycling speed was 2 km/h faster than Irene. At 10 20, Zoe caught up with Irene. Find the cycling speed of each cyclist.
- Irene
- Zoe
(a)
Duration that Zoe cycled from 06 50 to 10 20
= 3
3060 = 3
12 h
Distance that Zoe cycled more than Irene
= 3
12 x 2
= 7 km
However, since Irene left 30 minutes earlier than Zoe and Zoe caught up with Irene, it means that Irene has cycled 7 km in 30 min.
1 h = 60 min
30 min = 30 ÷ 60 =
12 h
Irene's cycling speed
= 7 ÷
12 = 7 x
21 = 14 km/h
(b)
Zoe's cycling speed
= 14 + 2
= 16 km/h
Answer(s): (a) 14 km/h ; (b) 16 km/h
